Caramelized Onion and Gruyere Tart
This Caramelized Onion and Gruyere Tart combines the sweetness of slow-cooked onions with the richness of Gruyere cheese, nestled in a buttery pastry crust. Perfect for a luxurious breakfast, a sophisticated appetizer, or a light dinner.
Equipment
- Skillet
- Tart Pan
- Oven
- Mixing bowl
- Measuring cups and spoons
- Knife
- Cutting board
Ingredients
For the Pastry:
- 1 1/4 cups all-purpose flour 150 g
- 1/2 tsp salt 2.5 g
- 1/2 cup unsalted butter, chilled and diced 113 g
- 3-4 tbsp ice water 45-60 ml
For the Filling:
- 3 tbsp olive oil 45 ml
- 2 large onions, thinly sliced about 500 g total
- 1 tsp sugar 4 g
- 1/2 tsp salt 2.5 g
- 1/4 tsp black pepper 1 g
- 1 cup Gruyere cheese, shredded 100 g
- 2 large eggs
- 1 cup heavy cream 240 ml
- 1 tsp fresh thyme leaves 1 g
Instructions
- Start by making the pastry. In a mixing bowl, combine the flour and salt. Add the chilled, diced butter and work it into the flour with your fingers until the mixture resembles coarse breadcrumbs. Gradually add ice water, stirring until the dough comes together. Form into a disc, wrap in plastic, and chill for at least 30 minutes.
- Preheat your oven to 375°F (190°C). On a floured surface, roll out the chilled dough into a 12-inch circle. Press the dough into a 9-inch tart pan, trimming any excess. Prick the bottom with a fork and set aside.
- For the filling, heat olive oil in a large skillet over medium heat. Add the sliced onions, sugar, salt, and pepper. Cook, stirring occasionally, until onions are deeply caramelized, about 30-40 minutes. Remove from heat and let cool slightly.
- Sprinkle half of the shredded Gruyere cheese onto the bottom of the tart shell. Spread the caramelized onions over the cheese.
- In a bowl, whisk together the eggs, heavy cream, and thyme. Pour this mixture over the onions. Top with the remaining Gruyere cheese.
- Bake the tart for 25-30 minutes, or until the filling is set and the top is golden brown. Let it cool for a few minutes before serving.
Notes
This tart can be served warm or at room temperature, making it a versatile addition to any meal.
If preferred, store-bought pastry dough can be used to save time.
The tart can be made ahead and reheated before serving.
Pair with a light salad for a complete meal.