Description
This Caramelized Onion Tart features a buttery, flaky crust filled with sweet, richly caramelized onions and a creamy, cheesy custard. Perfectly balanced with Gruyère or Parmesan cheese, this savory tart is ideal for both casual lunches and elegant gatherings. Its warm, comforting flavors and easy preparation make it a versatile dish suitable for parties or a cozy meal at home.
Ingredients
For the Crust
- 200 g all-purpose flour
- 100 g cold unsalted butter, cut into cubes
- 1 egg
- A pinch of salt
- 1-2 tbsp cold water
For the Filling
- 3-4 large onions (about 500 g), sliced into thin half-rings
- 30 g unsalted butter
- 100 ml heavy cream (20-30% fat)
- 2 eggs
- 100 g hard cheese such as Gruyère, Parmesan, or Cheddar, grated
- Salt and pepper to taste
- A pinch of nutmeg (optional)
Instructions
- Prepare the Crust: In a large bowl, combine the flour, salt, and cold butter cubes. Rub the mixture with your fingers until it resembles fine breadcrumbs. Add the egg and cold water, kneading just until the dough comes together. Shape the dough into a ball, wrap it in cling film, and refrigerate for 30 minutes.
- Caramelize the Onions: Slice the onions into thin half-rings. Melt the butter in a pan over medium heat and sauté the onions for about 20 minutes until they are soft and caramelized, stirring frequently to prevent burning.
- Make the Filling Mixture: In a bowl, whisk together the eggs and heavy cream. Add the grated cheese, salt, pepper, and nutmeg if using. Stir well to combine all ingredients evenly.
- Pre-bake the Crust: Roll out the chilled dough and fit it into a 23 cm tart pan. Press the edges and prick the base with a fork. Cover the crust with parchment paper, add pie weights or dried beans, and blind bake at 180°C (350°F) for 10 minutes.
- Assemble and Bake the Tart: Remove the weights and parchment from the crust. Spread the caramelized onions evenly over the pre-baked crust, then pour the cheese and cream mixture on top. Bake for 25-30 minutes at 180°C (350°F) until the filling is golden and set.
- Cool and Serve: Let the tart cool slightly before slicing. Serve warm or cold for the best flavor and texture, making it ideal for parties or casual meals.
Notes
- Blind baking the crust prevents it from becoming soggy once the filling is added.
- Use a mix of cheeses like Gruyère and Parmesan for a deeper flavor.
- The tart can be served warm or at room temperature, making it great for entertaining.
- For a dairy-free option, substitute butter and cream with plant-based alternatives.
- Store leftovers covered in the refrigerator for up to 2 days and reheat gently before serving.
- Prep Time: 40 minutes
- Cook Time: 50 minutes
- Category: Savory Tart
- Method: Baking
- Cuisine: French
