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If you're seeking a dish that embodies sophistication and comfort in equal measure, look no further than the Caramelized Onion & Gruyère Tart. This savory tart is a culinary masterpiece, marrying the sweetness of slowly caramelized onions with the nutty, rich flavor of Gruyère cheese. Whether you're hosting a fancy brunch, preparing a delightful appetizer for guests, or simply indulging in a light dinner, this tart fits the bill perfectly. Its flaky puff pastry crust serves as the ideal vessel for the creamy filling, making each bite a harmonious blend of textures and flavors.

Caramelized Onion & Gruyère Tart – Elegant & Delicious!

Discover the perfect balance of sophistication and comfort with this Caramelized Onion & Gruyère Tart. This savory delight features a flaky puff pastry crust filled with sweet, slowly caramelized onions and creamy Gruyère cheese, creating a rich and satisfying dish. Ideal for brunches, appetizers, or light dinners, this tart is not only delicious but also versatile. Follow our step-by-step guide to impress your friends and family with this culinary masterpiece. Enjoy it warm or at room temperature, paired with a crisp salad or a glass of wine for a truly delightful dining experience.
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Ingredients
  

1 sheet of puff pastry (thawed)

2 large yellow onions, thinly sliced

2 tablespoons unsalted butter

1 tablespoon olive oil

1 teaspoon sugar

1 teaspoon fresh thyme leaves (or ½ teaspoon dried thyme)

Salt and pepper to taste

1 cup Gruyère cheese, shredded

2 eggs

1 cup heavy cream

1 tablespoon Dijon mustard

Fresh parsley (for garnish)

Instructions
 

Preheat the Oven: Preheat your oven to 400°F (200°C).

    Caramelize the Onions: In a large skillet over medium heat, melt the butter with the olive oil. Add the sliced onions and stir to coat. Sprinkle with sugar, salt, and pepper. Cook slowly, stirring occasionally, until the onions are soft and caramelized, about 20-25 minutes. Add thyme in the last 5 minutes of cooking. Once done, remove from heat and let cool slightly.

      Prepare the Puff Pastry: Roll out the thawed puff pastry on a floured surface to fit your tart pan (approximately 11 inches). Gently transfer the pastry to the pan, trimming any excess that hangs over the edges. Prick the bottom with a fork to prevent bubbling.

        Blind Bake the Tart: Line the pastry with parchment paper, fill with pie weights or dried beans, and blind bake for 15 minutes. Remove the weights and parchment, and bake for an additional 5 minutes until slightly golden. Set aside to cool.

          Assemble the Filling: In a mixing bowl, whisk together the eggs, heavy cream, Dijon mustard, salt, and pepper. Stir in the shredded Gruyère cheese and the cooled caramelized onions until well combined.

            Bake the Tart: Pour the filling mixture into the cooled puff pastry shell. Bake for 25-30 minutes, or until the filling is set and the top is slightly golden.

              Cool and Serve: Allow the tart to cool for 10 minutes before slicing. Garnish with fresh parsley and serve warm or at room temperature.

                Prep Time, Total Time, Servings: 20 mins | 1 hour | 6 servings