Description
An elegant yet effortless upside down tart combining sweet caramelized onions with creamy, melt-in-your-mouth brie cheese, wrapped in a flaky buttery pastry. Perfect for brunch, appetizers, or a vegetarian main dish, this tart offers balanced rich flavors and impressive presentation.
Ingredients
Scale
For the Tart Dough
- 1 1/4 cups all-purpose flour (or gluten-free flour blend for gluten-free option)
- 1/2 cup (1 stick) cold unsalted butter, cut into small pieces
- 2–3 tablespoons cold water
- 1 egg (for egg wash)
- Salt, a pinch
For the Filling
- 3–4 large yellow or sweet onions, thinly sliced
- 2 tablespoons olive oil
- 1 tablespoon brown sugar
- Salt, to taste
- Freshly ground black pepper, to taste
- 8 oz brie cheese, sliced thinly into wedges or rounds
- 2–3 sprigs fresh thyme
Instructions
- Prepare the Caramelized Onions: Thinly slice the onions and gently cook them in olive oil over medium-low heat. Stir frequently and add brown sugar, salt, and freshly ground black pepper. Slowly cook for 30-40 minutes, until onions become rich golden brown and jammy.
- Make the Tart Dough: While onions cook, combine all-purpose flour and cold unsalted butter in a bowl. Cut butter into flour until the mixture resembles coarse crumbs. Add cold water gradually and mix just until dough comes together. Form into a disk, wrap, and chill in the refrigerator for at least 30 minutes.
- Assemble the Tart: Roll out chilled dough to fit the tart pan. Spread the caramelized onions evenly over the bottom to form the upside-down topping. Arrange thin slices of brie cheese over the onions. Add fresh thyme sprigs on top for fragrance and flavor.
- Bake the Tart: Cover filling with rolled-out pastry, fold edges neatly and trim excess. Brush top with beaten egg wash for a golden finish. Bake in a preheated oven at 375°F (190°C) for 30-35 minutes until crust is golden and crisp.
- Invert and Serve: Remove tart from oven and let cool for about 10 minutes. Carefully flip it onto a serving plate so the caramelized onion and brie are displayed on top. Serve warm to enjoy the creamy texture and rich flavors.
Notes
- Caramelize onions slowly over low heat to develop deep sweetness without burning.
- Use cold butter and water for dough to ensure a flaky, tender crust.
- Non-stick tart pan or greasing the pan prevents sticking during baking and inversion.
- Egg wash is key for a shiny, golden crust.
- Allow tart to cool slightly before flipping to avoid breaking the topping.
- Slice brie thinly to ensure even melting and integration with onions.
Nutrition
- Serving Size: 1 slice (1/6 of tart)
- Calories: 310
- Sugar: 7g
- Sodium: 180mg
- Fat: 22g
- Saturated Fat: 12g
- Unsaturated Fat: 8g
- Trans Fat: 0g
- Carbohydrates: 20g
- Fiber: 2g
- Protein: 6g
- Cholesterol: 55mg
Keywords: onion tart, brie tart, caramelized onions, vegetarian tart, savory tart, upside down tart, gluten free tart option
