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Caramelized Onion Gruyère Tart Flavorful Culinary Delight

by on December 16, 2024

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Get ready to indulge in a rich culinary experience with my Caramelized Onion Gruyère Tart! This delightful dish features sweet, buttery onions and nutty Gruyère cheese, all wrapped in crisp pastry. Whether you make it for a special occasion or a cozy dinner, this tart is sure to impress. Dive into this article for a step-by-step guide to making your own delicious creation, complete with tips, tricks, and variations!

To create a tasty Caramelized Onion Gruyère Tart, you need: - 1 sheet of puff pastry, thawed - 2 large onions, thinly sliced - 2 tablespoons extra virgin olive oil - 1 tablespoon balsamic vinegar - ½ teaspoon granulated sugar - Sea salt and freshly cracked black pepper to taste - 1 cup Gruyère cheese, freshly grated - 2 large eggs - 1 cup heavy cream - Fresh thyme leaves for garnish Each ingredient plays a key role. The puff pastry forms a flaky base. Onions bring sweetness when caramelized. Gruyère cheese adds a rich, nutty flavor. Eggs and cream give the tart a creamy texture. You can enhance your tart with these garnishes: - Fresh thyme leaves - A drizzle of balsamic glaze - A sprinkle of crushed red pepper flakes These add freshness and a pop of color. They also boost the flavor profile. If you need to swap ingredients, try these options: - Use cheddar cheese instead of Gruyère for a sharper taste. - Swap balsamic vinegar with red wine vinegar for a different tang. - Replace heavy cream with half-and-half for a lighter filling. These substitutions maintain the tart's deliciousness while catering to dietary needs. Feel free to mix and match to fit your taste. {{ingredient_image_2}} 1. Start by preheating your oven to 400°F (200°C). This step is key for a crispy crust. 2. Line your tart pan with parchment paper. This makes it easier to remove the tart later. 3. Slice two large onions thinly. Aim for even slices to cook them uniformly. 4. Heat two tablespoons of extra virgin olive oil in a large skillet over medium heat. 5. Add the sliced onions and a pinch of sea salt. This helps draw out moisture from the onions. 6. Cook the onions for 15-20 minutes. Stir occasionally until they turn golden brown and soft. 7. Mix in one tablespoon of balsamic vinegar and half a teaspoon of granulated sugar. This adds a sweet depth. 8. Cook for another five minutes. The onions should become sticky and caramelized. Remove from heat and allow to cool slightly. 9. Lightly flour your work surface and roll out the puff pastry. Make it large enough for the tart pan. 10. Carefully place the pastry in the tart pan. Press it against the bottom and sides. 11. Prick the pastry bottom with a fork. This prevents bubbling during baking. 12. Spread the caramelized onions evenly over the pastry base. 13. Sprinkle one cup of freshly grated Gruyère cheese over the onions. Use a generous amount for flavor. 14. In a bowl, whisk together two large eggs and one cup of heavy cream. Make it smooth and creamy. 15. Season this mixture with sea salt and freshly cracked black pepper. Pour it over the cheese and onions. 16. Place the tart in the oven and bake for 25-30 minutes. Look for a golden crust and set filling. 17. Once baked, remove the tart from the oven. Let it cool for about 10 minutes before slicing. 18. Just before serving, add fresh thyme leaves on top for a lovely aroma. - Use fresh Gruyère cheese for the best flavor. Grate it yourself if possible. - Make sure the onions are fully caramelized. This adds a rich, sweet flavor. - Allow the tart to cool slightly for easier slicing. This helps the filling set. - For a beautiful presentation, serve slices on individual plates with thyme on top. - Pair with a light side salad dressed in vinaigrette to balance the richness. To get sweet and rich caramelized onions, focus on low heat. Start by adding sliced onions to a hot pan with olive oil. A pinch of sea salt helps draw out moisture. Stir every few minutes. After about 20 minutes, your onions should turn a deep golden brown. Adding balsamic vinegar and sugar near the end boosts flavor and sticky texture. Cook for five more minutes. Your onions will be sweet and caramelized, perfect for the tart. Puff pastry should be flaky and airy. After rolling it out, ensure it fits snugly in the tart pan. Pricking the bottom with a fork prevents bubbling. Bake it until the edges are golden brown. This ensures a crisp base that supports the filling. If you want extra crunch, brush the pastry with egg wash before baking. This tart shines in any season. In spring, serve it with a fresh green salad. In summer, add sliced tomatoes for a bright touch. In fall and winter, pair it with roasted vegetables. Adding a light vinaigrette enhances the flavors. For special occasions, sprinkle fresh thyme on top before serving. Enjoy the blend of flavors with a glass of white wine for a delightful experience. Pro Tips Use Sweet Onions: For the best flavor, opt for sweet onions, such as Vidalia or Walla Walla, which enhance the caramelization process. Chill the Puff Pastry: Before rolling out, chill the puff pastry for about 10-15 minutes to ensure it stays flaky during baking. Don’t Rush the Onions: Take your time when caramelizing the onions; low and slow cooking enhances their natural sweetness and flavor. Experiment with Cheeses: While Gruyère is delicious, feel free to mix in other cheeses like aged cheddar or fontina for a unique flavor profile. {{image_4}} You can switch Gruyère for other cheeses to change the flavor. Here are some great options: - Fontina: This cheese melts well and has a rich taste. - Comté: Similar to Gruyère, it adds a nutty flavor. - Goat Cheese: For a tangy kick, crumbled goat cheese works well. - Cheddar: A sharp cheddar adds a bold touch and melts nicely. Feel free to mix and match cheeses for a fun flavor experience. Adding vegetables can give your tart a fresh twist. Here are some tasty choices: - Spinach: Adds color and nutrients. Sauté it before adding. - Mushrooms: Sautéed mushrooms add a rich, earthy flavor. - Zucchini: Thinly sliced zucchini brings a light taste. - Roasted Peppers: Sweet roasted peppers can add depth. These add-ins can balance the sweetness of the onions. You can use more than just puff pastry for the base. Consider these options: - Shortcrust Pastry: This gives a crumbly, buttery feel. - Phyllo Dough: For a lighter, crispier texture, use layers of phyllo. - Whole Wheat Pastry: A healthier choice that adds a nutty flavor. - Savory Cracker Crust: Blend crushed crackers with butter for a unique base. Exploring different pastries can keep your tart exciting and fresh. To store leftovers, let the tart cool first. Wrap it tightly in plastic wrap or aluminum foil. You can also place it in an airtight container. This keeps the flavors fresh and the crust from getting soggy. Store the tart in the fridge for up to three days. When you're ready to enjoy leftovers, preheat your oven to 350°F (175°C). Place the tart on a baking sheet. Heat for about 15-20 minutes. This warms the tart and makes the crust crispy again. Check to ensure it is heated through before serving. You can freeze the tart for future meals. First, let the tart cool completely. Wrap it well in plastic wrap, then in foil. It can last in the freezer for up to three months. To reheat, thaw it in the fridge overnight. Then follow the reheating instructions above for best results. Yes, you can make the tart ahead. Prepare the tart, but don't bake it. Cover it well with plastic wrap and keep it in the fridge. You can store it for up to 24 hours. When ready to serve, bake it as directed. This saves time and helps the flavors meld. This tart pairs well with a light salad. A simple green salad with vinaigrette works nicely. You can also serve it with roasted vegetables or a bowl of soup. These options balance the rich flavors of the tart. Fresh herbs like thyme add a nice touch too. You can tell the tart is done when the edges are golden brown. The filling should be set and not jiggly. If you insert a knife, it should come out clean. If the pastry looks pale, it needs more time. Trust your eyes and nose; the aroma should be delicious! This blog post covered the ingredients, steps, and tips for making a delicious Caramelized Onion Gruyère Tart. We explored essential ingredients, optional garnishes, and easy substitutions. I shared preparation and cooking tips to help you achieve the perfect texture. We also discussed variations, storage, and answered common questions about the tart. In summary, this tart is easy and versatile. You can impress family and friends with this delightful dish wherever you serve it. Enjoy your cooking, and make this tart your own!

Why I Love This Recipe

  1. Delicious Flavor Combination: The sweetness of caramelized onions perfectly complements the rich, nutty Gruyère cheese, creating a satisfying and comforting flavor profile.
  2. Easy to Prepare: With just a few simple steps and readily available ingredients, this tart is a breeze to make, even for beginner cooks.
  3. Versatile Dish: This tart can be served warm or at room temperature, making it a great option for brunch, lunch, or as an appetizer for dinner parties.
  4. Elegant Presentation: The golden-brown pastry and garnished thyme leaves make this dish visually appealing, perfect for impressing guests at any gathering.

Ingredients

Essential Ingredients for Caramelized Onion Gruyère Tart

To create a tasty Caramelized Onion Gruyère Tart, you need:

– 1 sheet of puff pastry, thawed

– 2 large onions, thinly sliced

– 2 tablespoons extra virgin olive oil

– 1 tablespoon balsamic vinegar

– ½ teaspoon granulated sugar

– Sea salt and freshly cracked black pepper to taste

– 1 cup Gruyère cheese, freshly grated

– 2 large eggs

– 1 cup heavy cream

– Fresh thyme leaves for garnish

Each ingredient plays a key role. The puff pastry forms a flaky base. Onions bring sweetness when caramelized. Gruyère cheese adds a rich, nutty flavor. Eggs and cream give the tart a creamy texture.

Optional Garnishes

You can enhance your tart with these garnishes:

– Fresh thyme leaves

– A drizzle of balsamic glaze

– A sprinkle of crushed red pepper flakes

These add freshness and a pop of color. They also boost the flavor profile.

Ingredient Substitutions

If you need to swap ingredients, try these options:

– Use cheddar cheese instead of Gruyère for a sharper taste.

– Swap balsamic vinegar with red wine vinegar for a different tang.

– Replace heavy cream with half-and-half for a lighter filling.

These substitutions maintain the tart’s deliciousness while catering to dietary needs. Feel free to mix and match to fit your taste.

Step-by-Step Instructions

Preparation Steps

1. Start by preheating your oven to 400°F (200°C). This step is key for a crispy crust.

2. Line your tart pan with parchment paper. This makes it easier to remove the tart later.

3. Slice two large onions thinly. Aim for even slices to cook them uniformly.

4. Heat two tablespoons of extra virgin olive oil in a large skillet over medium heat.

5. Add the sliced onions and a pinch of sea salt. This helps draw out moisture from the onions.

6. Cook the onions for 15-20 minutes. Stir occasionally until they turn golden brown and soft.

7. Mix in one tablespoon of balsamic vinegar and half a teaspoon of granulated sugar. This adds a sweet depth.

8. Cook for another five minutes. The onions should become sticky and caramelized. Remove from heat and allow to cool slightly.

Cooking Process

9. Lightly flour your work surface and roll out the puff pastry. Make it large enough for the tart pan.

10. Carefully place the pastry in the tart pan. Press it against the bottom and sides.

11. Prick the pastry bottom with a fork. This prevents bubbling during baking.

12. Spread the caramelized onions evenly over the pastry base.

13. Sprinkle one cup of freshly grated Gruyère cheese over the onions. Use a generous amount for flavor.

14. In a bowl, whisk together two large eggs and one cup of heavy cream. Make it smooth and creamy.

15. Season this mixture with sea salt and freshly cracked black pepper. Pour it over the cheese and onions.

16. Place the tart in the oven and bake for 25-30 minutes. Look for a golden crust and set filling.

17. Once baked, remove the tart from the oven. Let it cool for about 10 minutes before slicing.

18. Just before serving, add fresh thyme leaves on top for a lovely aroma.

Tips for Perfect Baked Tart

– Use fresh Gruyère cheese for the best flavor. Grate it yourself if possible.

– Make sure the onions are fully caramelized. This adds a rich, sweet flavor.

– Allow the tart to cool slightly for easier slicing. This helps the filling set.

– For a beautiful presentation, serve slices on individual plates with thyme on top.

– Pair with a light side salad dressed in vinaigrette to balance the richness.

Tips & Tricks

How to Perfect Caramelization

To get sweet and rich caramelized onions, focus on low heat. Start by adding sliced onions to a hot pan with olive oil. A pinch of sea salt helps draw out moisture. Stir every few minutes. After about 20 minutes, your onions should turn a deep golden brown. Adding balsamic vinegar and sugar near the end boosts flavor and sticky texture. Cook for five more minutes. Your onions will be sweet and caramelized, perfect for the tart.

Achieving the Right Texture for Puff Pastry

Puff pastry should be flaky and airy. After rolling it out, ensure it fits snugly in the tart pan. Pricking the bottom with a fork prevents bubbling. Bake it until the edges are golden brown. This ensures a crisp base that supports the filling. If you want extra crunch, brush the pastry with egg wash before baking.

Seasonal Suggestions for Serving

This tart shines in any season. In spring, serve it with a fresh green salad. In summer, add sliced tomatoes for a bright touch. In fall and winter, pair it with roasted vegetables. Adding a light vinaigrette enhances the flavors. For special occasions, sprinkle fresh thyme on top before serving. Enjoy the blend of flavors with a glass of white wine for a delightful experience.

Pro Tips

  1. Use Sweet Onions: For the best flavor, opt for sweet onions, such as Vidalia or Walla Walla, which enhance the caramelization process.
  2. Chill the Puff Pastry: Before rolling out, chill the puff pastry for about 10-15 minutes to ensure it stays flaky during baking.
  3. Don’t Rush the Onions: Take your time when caramelizing the onions; low and slow cooking enhances their natural sweetness and flavor.
  4. Experiment with Cheeses: While Gruyère is delicious, feel free to mix in other cheeses like aged cheddar or fontina for a unique flavor profile.

Variations

Alternative Cheeses to Use

You can switch Gruyère for other cheeses to change the flavor. Here are some great options:

– Fontina: This cheese melts well and has a rich taste.

– Comté: Similar to Gruyère, it adds a nutty flavor.

– Goat Cheese: For a tangy kick, crumbled goat cheese works well.

– Cheddar: A sharp cheddar adds a bold touch and melts nicely.

Feel free to mix and match cheeses for a fun flavor experience.

Vegetable Add-ins for a Unique Twist

Adding vegetables can give your tart a fresh twist. Here are some tasty choices:

– Spinach: Adds color and nutrients. Sauté it before adding.

– Mushrooms: Sautéed mushrooms add a rich, earthy flavor.

– Zucchini: Thinly sliced zucchini brings a light taste.

– Roasted Peppers: Sweet roasted peppers can add depth.

These add-ins can balance the sweetness of the onions.

Different Pastry Options

You can use more than just puff pastry for the base. Consider these options:

– Shortcrust Pastry: This gives a crumbly, buttery feel.

– Phyllo Dough: For a lighter, crispier texture, use layers of phyllo.

– Whole Wheat Pastry: A healthier choice that adds a nutty flavor.

– Savory Cracker Crust: Blend crushed crackers with butter for a unique base.

Exploring different pastries can keep your tart exciting and fresh.

Storage Information

How to Store Leftovers

To store leftovers, let the tart cool first. Wrap it tightly in plastic wrap or aluminum foil. You can also place it in an airtight container. This keeps the flavors fresh and the crust from getting soggy. Store the tart in the fridge for up to three days.

Reheating Instructions

When you’re ready to enjoy leftovers, preheat your oven to 350°F (175°C). Place the tart on a baking sheet. Heat for about 15-20 minutes. This warms the tart and makes the crust crispy again. Check to ensure it is heated through before serving.

Freezing the Tart for Later

You can freeze the tart for future meals. First, let the tart cool completely. Wrap it well in plastic wrap, then in foil. It can last in the freezer for up to three months. To reheat, thaw it in the fridge overnight. Then follow the reheating instructions above for best results.

FAQs

Can I make the tart ahead of time?

Yes, you can make the tart ahead. Prepare the tart, but don’t bake it. Cover it well with plastic wrap and keep it in the fridge. You can store it for up to 24 hours. When ready to serve, bake it as directed. This saves time and helps the flavors meld.

What to serve with Caramelized Onion Gruyère Tart?

This tart pairs well with a light salad. A simple green salad with vinaigrette works nicely. You can also serve it with roasted vegetables or a bowl of soup. These options balance the rich flavors of the tart. Fresh herbs like thyme add a nice touch too.

How do I know when the tart is fully baked?

You can tell the tart is done when the edges are golden brown. The filling should be set and not jiggly. If you insert a knife, it should come out clean. If the pastry looks pale, it needs more time. Trust your eyes and nose; the aroma should be delicious!

This blog post covered the ingredients, steps, and tips for making a delicious Caramelized Onion Gruyère Tart. We explored essential ingredients, optional garnishes, and easy substitutions. I shared preparation and cooking tips to help you achieve the perfect texture. We also discussed variations, storage, and answered common questions about the tart.

In summary, this tart is easy and versatile. You can impress family and friends with this delightful dish wherever you serve it. Enjoy your cooking, and make this tart your ow

To create a tasty Caramelized Onion Gruyère Tart, you need: - 1 sheet of puff pastry, thawed - 2 large onions, thinly sliced - 2 tablespoons extra virgin olive oil - 1 tablespoon balsamic vinegar - ½ teaspoon granulated sugar - Sea salt and freshly cracked black pepper to taste - 1 cup Gruyère cheese, freshly grated - 2 large eggs - 1 cup heavy cream - Fresh thyme leaves for garnish Each ingredient plays a key role. The puff pastry forms a flaky base. Onions bring sweetness when caramelized. Gruyère cheese adds a rich, nutty flavor. Eggs and cream give the tart a creamy texture. You can enhance your tart with these garnishes: - Fresh thyme leaves - A drizzle of balsamic glaze - A sprinkle of crushed red pepper flakes These add freshness and a pop of color. They also boost the flavor profile. If you need to swap ingredients, try these options: - Use cheddar cheese instead of Gruyère for a sharper taste. - Swap balsamic vinegar with red wine vinegar for a different tang. - Replace heavy cream with half-and-half for a lighter filling. These substitutions maintain the tart's deliciousness while catering to dietary needs. Feel free to mix and match to fit your taste. {{ingredient_image_2}} 1. Start by preheating your oven to 400°F (200°C). This step is key for a crispy crust. 2. Line your tart pan with parchment paper. This makes it easier to remove the tart later. 3. Slice two large onions thinly. Aim for even slices to cook them uniformly. 4. Heat two tablespoons of extra virgin olive oil in a large skillet over medium heat. 5. Add the sliced onions and a pinch of sea salt. This helps draw out moisture from the onions. 6. Cook the onions for 15-20 minutes. Stir occasionally until they turn golden brown and soft. 7. Mix in one tablespoon of balsamic vinegar and half a teaspoon of granulated sugar. This adds a sweet depth. 8. Cook for another five minutes. The onions should become sticky and caramelized. Remove from heat and allow to cool slightly. 9. Lightly flour your work surface and roll out the puff pastry. Make it large enough for the tart pan. 10. Carefully place the pastry in the tart pan. Press it against the bottom and sides. 11. Prick the pastry bottom with a fork. This prevents bubbling during baking. 12. Spread the caramelized onions evenly over the pastry base. 13. Sprinkle one cup of freshly grated Gruyère cheese over the onions. Use a generous amount for flavor. 14. In a bowl, whisk together two large eggs and one cup of heavy cream. Make it smooth and creamy. 15. Season this mixture with sea salt and freshly cracked black pepper. Pour it over the cheese and onions. 16. Place the tart in the oven and bake for 25-30 minutes. Look for a golden crust and set filling. 17. Once baked, remove the tart from the oven. Let it cool for about 10 minutes before slicing. 18. Just before serving, add fresh thyme leaves on top for a lovely aroma. - Use fresh Gruyère cheese for the best flavor. Grate it yourself if possible. - Make sure the onions are fully caramelized. This adds a rich, sweet flavor. - Allow the tart to cool slightly for easier slicing. This helps the filling set. - For a beautiful presentation, serve slices on individual plates with thyme on top. - Pair with a light side salad dressed in vinaigrette to balance the richness. To get sweet and rich caramelized onions, focus on low heat. Start by adding sliced onions to a hot pan with olive oil. A pinch of sea salt helps draw out moisture. Stir every few minutes. After about 20 minutes, your onions should turn a deep golden brown. Adding balsamic vinegar and sugar near the end boosts flavor and sticky texture. Cook for five more minutes. Your onions will be sweet and caramelized, perfect for the tart. Puff pastry should be flaky and airy. After rolling it out, ensure it fits snugly in the tart pan. Pricking the bottom with a fork prevents bubbling. Bake it until the edges are golden brown. This ensures a crisp base that supports the filling. If you want extra crunch, brush the pastry with egg wash before baking. This tart shines in any season. In spring, serve it with a fresh green salad. In summer, add sliced tomatoes for a bright touch. In fall and winter, pair it with roasted vegetables. Adding a light vinaigrette enhances the flavors. For special occasions, sprinkle fresh thyme on top before serving. Enjoy the blend of flavors with a glass of white wine for a delightful experience. Pro Tips Use Sweet Onions: For the best flavor, opt for sweet onions, such as Vidalia or Walla Walla, which enhance the caramelization process. Chill the Puff Pastry: Before rolling out, chill the puff pastry for about 10-15 minutes to ensure it stays flaky during baking. Don’t Rush the Onions: Take your time when caramelizing the onions; low and slow cooking enhances their natural sweetness and flavor. Experiment with Cheeses: While Gruyère is delicious, feel free to mix in other cheeses like aged cheddar or fontina for a unique flavor profile. {{image_4}} You can switch Gruyère for other cheeses to change the flavor. Here are some great options: - Fontina: This cheese melts well and has a rich taste. - Comté: Similar to Gruyère, it adds a nutty flavor. - Goat Cheese: For a tangy kick, crumbled goat cheese works well. - Cheddar: A sharp cheddar adds a bold touch and melts nicely. Feel free to mix and match cheeses for a fun flavor experience. Adding vegetables can give your tart a fresh twist. Here are some tasty choices: - Spinach: Adds color and nutrients. Sauté it before adding. - Mushrooms: Sautéed mushrooms add a rich, earthy flavor. - Zucchini: Thinly sliced zucchini brings a light taste. - Roasted Peppers: Sweet roasted peppers can add depth. These add-ins can balance the sweetness of the onions. You can use more than just puff pastry for the base. Consider these options: - Shortcrust Pastry: This gives a crumbly, buttery feel. - Phyllo Dough: For a lighter, crispier texture, use layers of phyllo. - Whole Wheat Pastry: A healthier choice that adds a nutty flavor. - Savory Cracker Crust: Blend crushed crackers with butter for a unique base. Exploring different pastries can keep your tart exciting and fresh. To store leftovers, let the tart cool first. Wrap it tightly in plastic wrap or aluminum foil. You can also place it in an airtight container. This keeps the flavors fresh and the crust from getting soggy. Store the tart in the fridge for up to three days. When you're ready to enjoy leftovers, preheat your oven to 350°F (175°C). Place the tart on a baking sheet. Heat for about 15-20 minutes. This warms the tart and makes the crust crispy again. Check to ensure it is heated through before serving. You can freeze the tart for future meals. First, let the tart cool completely. Wrap it well in plastic wrap, then in foil. It can last in the freezer for up to three months. To reheat, thaw it in the fridge overnight. Then follow the reheating instructions above for best results. Yes, you can make the tart ahead. Prepare the tart, but don't bake it. Cover it well with plastic wrap and keep it in the fridge. You can store it for up to 24 hours. When ready to serve, bake it as directed. This saves time and helps the flavors meld. This tart pairs well with a light salad. A simple green salad with vinaigrette works nicely. You can also serve it with roasted vegetables or a bowl of soup. These options balance the rich flavors of the tart. Fresh herbs like thyme add a nice touch too. You can tell the tart is done when the edges are golden brown. The filling should be set and not jiggly. If you insert a knife, it should come out clean. If the pastry looks pale, it needs more time. Trust your eyes and nose; the aroma should be delicious! This blog post covered the ingredients, steps, and tips for making a delicious Caramelized Onion Gruyère Tart. We explored essential ingredients, optional garnishes, and easy substitutions. I shared preparation and cooking tips to help you achieve the perfect texture. We also discussed variations, storage, and answered common questions about the tart. In summary, this tart is easy and versatile. You can impress family and friends with this delightful dish wherever you serve it. Enjoy your cooking, and make this tart your own!

Caramelized Onion Gruyère Tart

A delicious tart featuring caramelized onions and Gruyère cheese, perfect for any occasion.
Print Recipe Pin Recipe
Prep Time 15 minutes
Cook Time 30 minutes
Total Time 50 minutes
Course Appetizer
Cuisine French
Servings 6
Calories 350 kcal

Ingredients
  

  • 1 sheet puff pastry, thawed
  • 2 large onions, thinly sliced
  • 2 tablespoons extra virgin olive oil
  • 1 tablespoon balsamic vinegar
  • 0.5 teaspoon granulated sugar
  • to taste sea salt and freshly cracked black pepper
  • 1 cup Gruyère cheese, freshly grated
  • 2 large eggs
  • 1 cup heavy cream
  • for garnish fresh thyme leaves

Instructions
 

  • Preheat your oven to 400°F (200°C) and line a tart pan (about 10 inches in diameter) with parchment paper for easier removal if desired.
  • In a large skillet, heat the extra virgin olive oil over medium heat. Add the sliced onions along with a pinch of sea salt to help draw out their moisture.
  • Sauté the onions, stirring occasionally, for about 15-20 minutes, or until they become wonderfully soft and achieve a deep golden brown color.
  • Stir in the balsamic vinegar and granulated sugar, allowing them to integrate into the onions. Continue to cook for an additional 5 minutes, stirring frequently, until the onions are caramelized and sticky. Remove from the heat and allow to cool slightly.
  • On a lightly floured surface, roll out the puff pastry into a circle large enough to fit your tart pan. Carefully transfer the pastry into the pan, pressing it against the bottom and sides, and prick the bottom with a fork to prevent bubbling during baking.
  • Evenly distribute the caramelized onions over the puff pastry base, ensuring they are well spread. Then sprinkle the freshly grated Gruyère cheese generously over the onions.
  • In a separate bowl, whisk together the eggs and heavy cream until smooth. Season the mixture with sea salt and freshly cracked black pepper. Pour this creamy mixture over the cheese and onions in the tart shell, allowing it to settle naturally.
  • Place the tart in the preheated oven and bake for 25-30 minutes. The tart is ready when the filling is set, and the pastry edges are a beautiful golden brown.
  • Once baked, remove the tart from the oven and let it cool for about 10 minutes before slicing to allow the filling to firm up slightly.
  • Just before serving, garnish the tart with fresh thyme leaves for an aromatic finish.

Notes

For an elegant serving, place slices of the tart on individual plates, garnishing with a small sprig of thyme on top. Optionally, pair with a light side salad dressed in a simple vinaigrette to complement the rich flavors of the tart.
Keyword caramelized, gruyère, onion, pastry, tart

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