Jul 14 2026
RestaurantsThe Castle, Black RockHot Onion Tart Recipe

Hot Onion Tart Recipe

Time1h 30m
Serves6

Make Hot Onion Tart Recipe in just 1h 30m. Get the full recipe with step-by-step instructions at pekinthechef.com.

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Ingredients

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Crust

Filling

Method

Crust Preparation

  1. 1

    Make the Dough

    In a large bowl, combine the all-purpose flour and salt. Cut in the unsalted butter until the mixture resembles coarse crumbs. Gradually add ice water, 1 tablespoon at a time, mixing until the dough comes together.

  2. 2

    Chill the Dough

    Shape the dough into a disc, wrap in plastic wrap, and refrigerate for at least 30 minutes.

  3. 3

    Roll Out the Dough

    On a floured surface, roll out the chilled dough to fit a 9-inch tart pan. Transfer the dough to the pan, pressing it into the edges. Trim any excess dough.

  4. 4

    Pre-bake the Crust

    Preheat the oven to 375°F (190°C). Prick the bottom of the crust with a fork, line it with parchment paper, and fill with pie weights or dried beans. Bake for 15 minutes, then remove the weights and parchment and bake for another 10 minutes until lightly golden.

Filling Preparation

  1. 5

    Caramelize the Onions

    Peel and slice the onions thinly. In a large skillet, heat the olive oil over medium heat. Add the onions and cook, stirring occasionally, until they are caramelized and golden brown, about 25-30 minutes.

  2. 6

    Prepare the Egg Mixture

    In a mixing bowl, whisk together the eggs, heavy cream, black pepper, and fresh thyme until well combined.

  3. 7

    Combine and Assemble

    Once the onions are caramelized, spread them evenly over the pre-baked tart crust. Pour the egg mixture over the onions, then top with grated gruyere cheese.

  4. 8

    Bake the Tart

    Bake the tart in the preheated oven for 30-35 minutes, or until the filling is set and the cheese is bubbly and golden.

  5. 9

    Cool and Serve

    Remove the tart from the oven and let it cool for a few minutes before slicing. Serve warm or at room temperature.

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