Description
A delicious French-inspired beefsteak tomato tart featuring a flaky puff pastry crust topped with sweet caramelized onions, fresh thyme, and gooey Gruyère cheese. This savory tart is perfect as an appetizer or light meal, baked until golden and garnished with fresh herbs.
Ingredients
Scale
Pastry and Base
- 1 sheet puff pastry, thawed
- 1 tablespoon Dijon mustard
- 1 egg, beaten (for egg wash)
Toppings
- 2 large beefsteak tomatoes, sliced 1/4-inch thick
- 2 tablespoons olive oil
- 2 large yellow onions, thinly sliced
- 1 teaspoon fresh thyme leaves (or 1/2 teaspoon dried)
- 1 cup shredded Gruyère cheese (or Swiss cheese)
- 1/4 cup grated Parmesan cheese
- 1/4 teaspoon salt
- 1/4 teaspoon black pepper
- Fresh thyme sprigs, for garnish (optional)
Instructions
- Caramelize Onions: Heat olive oil in a large skillet over medium heat. Add the thinly sliced onions and cook slowly for 20–25 minutes, stirring occasionally until onions are golden and caramelized. Stir in thyme leaves, salt, and pepper; then remove from heat.
- Prepare Puff Pastry: Preheat oven to 400°F (200°C). On a lightly floured surface, roll out puff pastry slightly and transfer to a parchment-lined baking sheet. Score a 1-inch border around the edges without cutting through and prick the center with a fork to prevent puffing.
- Assemble Tart: Spread Dijon mustard evenly within the scored border. Top with caramelized onions, then sprinkle with shredded Gruyère cheese. Arrange tomato slices on top, overlapping slightly. Sprinkle with Parmesan cheese, salt, and pepper.
- Finishing Touches: Brush the pastry border with beaten egg to achieve a golden finish during baking.
- Bake Tart: Bake in preheated oven for 25–30 minutes until pastry is golden brown and crisp.
- Garnish and Serve: Remove from oven, garnish with fresh thyme sprigs if desired, and serve warm or at room temperature.
Notes
- To prevent soggy pastry, lightly salt the tomato slices and let them rest on paper towels for 10 minutes before layering.
- For variety, swap Gruyère with mozzarella or goat cheese.
