Description
This Caramelized Onion Tart is a deliciously savory French-inspired appetizer featuring sweet, slow-cooked onions on a flaky puff pastry base, topped with melted Gruyère and optional tangy goat cheese. Perfect for brunch or as an elegant starter, this tart offers a wonderful balance of rich flavors and textures.
Ingredients
Scale
For the Tart Base
- 1 sheet puff pastry, thawed
For the Caramelized Onions
- 2 tablespoons unsalted butter
- 1 tablespoon olive oil
- 3 large yellow onions, thinly sliced
- 1/2 teaspoon salt
- 1/2 teaspoon sugar
- 1 teaspoon fresh thyme leaves (or 1/4 teaspoon dried thyme)
- Freshly ground black pepper to taste
For the Topping
- 1/2 cup grated Gruyère or Swiss cheese
- 1/4 cup crumbled goat cheese or feta (optional)
- 1 egg, beaten (for egg wash)
Instructions
- Preheat Oven: Preheat your oven to 400°F (200°C) to prepare for baking the tart.
- Caramelize Onions: In a large skillet, melt the butter with the olive oil over medium heat. Add the thinly sliced onions, salt, and sugar. Cook slowly, stirring occasionally, for 25 to 30 minutes until the onions turn deeply golden and caramelized, releasing their natural sweetness.
- Add Thyme and Season: Stir in the fresh thyme leaves and season the onions with freshly ground black pepper to enhance the flavor.
- Prepare Puff Pastry: Roll out the thawed puff pastry on a lightly floured surface. Transfer it to a parchment-lined baking sheet. Lightly score a 1/2-inch border around the edges of the pastry and prick the center with a fork to prevent it from puffing excessively during baking.
- Egg Wash: Brush the scored border of the pastry with the beaten egg to help it brown nicely and create a defined edge.
- Assemble Tart: Spread the caramelized onions evenly within the scored border on the puff pastry. Sprinkle the grated Gruyère cheese evenly over the onions, and if using, crumble the goat cheese over the top.
- Bake: Place the tart in the preheated oven and bake for 20 to 25 minutes, or until the edges of the pastry are golden brown and crisp, and the cheese has melted beautifully.
- Cool and Serve: Allow the tart to cool slightly before slicing. Serve warm or at room temperature, ideal as an appetizer, brunch item, or alongside a green salad.
Notes
- Serve as an appetizer, brunch dish, or alongside a fresh green salad for a complete meal.
- You can prepare the caramelized onions a day ahead and store them in the refrigerator to save time on the day of serving.
- Use goat cheese or feta for a tangier flavor, or omit for a milder taste.
- If you prefer a vegetarian option without cheese, omit the cheeses entirely, though the tart will be less rich.
Nutrition
- Serving Size: 1 slice
- Calories: 280
- Sugar: 5g
- Sodium: 310mg
- Fat: 18g
- Saturated Fat: 9g
- Unsaturated Fat: 8g
- Trans Fat: 0g
- Carbohydrates: 22g
- Fiber: 2g
- Protein: 6g
- Cholesterol: 40mg
