Description
This savory tart features sweet caramelized onions paired with rich Gruyere cheese, all nestled in a flaky pastry crust. Perfect as an appetizer or a light meal.
Ingredients
Scale
- 1 sheet of puff pastry, thawed
- 3 large onions, thinly sliced
- 2 tablespoons olive oil
- 1 tablespoon butter
- 1 teaspoon fresh thyme leaves
- Salt and pepper to taste
- 1 cup Gruyere cheese, grated
- 1 egg, beaten (for egg wash)
- 1 tablespoon balsamic vinegar (optional)
Instructions
- Preheat your oven to 400°F (200°C).
- In a large skillet, heat olive oil and butter over medium heat. Add the sliced onions and a pinch of salt.
- Cook the onions slowly, stirring occasionally, until they are caramelized and golden brown, about 25-30 minutes. Add thyme and balsamic vinegar, if using, and cook for an additional 2 minutes.
- Roll out the puff pastry on a floured surface to fit your tart pan. Place the pastry in the tart pan, trimming any excess.
- Spread the caramelized onions evenly over the pastry, then sprinkle the grated Gruyere cheese on top.
- Brush the edges of the pastry with the beaten egg.
- Bake in the preheated oven for 25-30 minutes, or until the pastry is golden brown and the cheese is bubbly.
- Let cool slightly before slicing and serving.
Notes
- For added flavor, you can mix in some cooked bacon or sautéed mushrooms with the onions.
- This tart can be served warm or at room temperature.
Nutrition
- Serving Size: 1 slice
- Calories: 210
- Sugar: 2
- Sodium: 200
- Fat: 14
- Saturated Fat: 7
- Carbohydrates: 17
- Fiber: 1
- Protein: 5
Keywords: caramelized onion tart, gruyere cheese tart, savory tart recipe, puff pastry tart, French onion tart