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french onion tart

This French Onion Tart features a golden, flaky pastry crust filled with caramelized onions, creamy cheese, and fresh herbs. Perfect as a main dish or an impressive appetizer, this tart combines sweet and savory flavors that are sure to please.
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Prep Time 30 minutes
Cook Time 40 minutes
Total Time 1 hour 10 minutes
Course Main Dish
Cuisine French
Servings 4 People
Calories 350 kcal

Equipment

  • 1 baking dish (9-inch round)
  • 1 large frying pan
  • 1 rolling pin
  • 1 mixing bowl
  • 1 whisk

Ingredients
  

  • 1 sheet pre-made puff pastry About 250g.
  • 4 large onions About 800g, thinly sliced.
  • 2 tablespoons olive oil
  • 2 tablespoons unsalted butter
  • 1 teaspoon salt
  • 1 teaspoon sugar
  • 2 cloves garlic Minced.
  • 3 large eggs
  • 200 ml heavy cream
  • 100 g Gruyère cheese Grated, or Swiss cheese.
  • 50 g Parmesan cheese Grated.
  • 1 tablespoon fresh thyme leaves Or 1 teaspoon dried thyme.
  • to taste freshly ground black pepper

Instructions
 

  • Preheat your oven to 375°F (190°C).
  • In a large frying pan, heat the olive oil and butter over medium heat.
  • Add the sliced onions, salt, and sugar to the pan. Cook, stirring frequently, for about 25-30 minutes, until the onions are deeply caramelized and golden brown. Add minced garlic in the last 2 minutes of cooking. Remove from heat and allow to cool slightly.
  • Roll out the puff pastry on a lightly floured surface to fit your baking dish. Press the pastry into the dish and trim the edges. Prick the base with a fork to prevent it from puffing up.
  • In a mixing bowl, whisk together the eggs, heavy cream, thyme, salt, and black pepper.
  • Once the onions have cooled slightly, spread them evenly over the pastry crust. Pour the egg and cream mixture over the onions.
  • Sprinkle the Gruyère and Parmesan cheeses on top.
  • Bake the tart in the preheated oven for about 30-35 minutes, or until the cheese is golden and the filling is set.
  • Remove from the oven and let it cool for a few minutes before slicing and serving.

Notes

You can add a splash of white wine to the onions while caramelizing for extra flavor.
This tart can be served warm or at room temperature and pairs well with a mixed green salad. Enjoy your delightful French Onion Tart!