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Classic Square Custard Tart (Crostata alla Crema)

This gorgeous, thick-cut dessert is a Square Custard Tart (often referred to in European baking as a Crostata alla Crema or a Parisian-style custard tart). It features a tall, crisp, buttery shortcrust pastry shell filled to the brim with a dense, rich vanilla pastry cream that sets perfectly enough to slice into neat squares.

Prep & Cook Details

• Prep Time: 30 minutes

• Cook Time: 45 minutes

• Chilling Time: 2 hours (essential for those clean, sharp slices!)

• Servings: 9 large square slices

• Equipment: 8×8 inch (20×20 cm) square tart pan or square springform pan

Ingredients

1. For the Shortcrust Pastry Case

• 250g All-purpose flour

• 125g Cold unsalted butter, cubed

• 80g Powdered sugar (icing sugar)

• 2 Egg yolks (from large eggs)

• 1-2 tbsp Ice-cold water

• A pinch of Salt

2. For the Ultra-Thick Custard Filling

• 600 ml Whole milk (or half-and-half for extra richness)

• 6 Large egg yolks

• 120g Granulated sugar

• 50g Cornstarch (gives it that firm, sliceable structure)

• 1 ½ tsp Pure vanilla extract or vanilla bean paste

• 30g Unsalted butter (stirred in at the end for a glossy finish)

Step-by-Step Instructions

Step 1: Make and Blind-Bake the Pastry Case

1. Combine dry ingredients: In a food processor or a large bowl, mix the flour, powdered sugar, and a pinch of salt.

2. Cut in the butter: Add the ice-cold, cubed butter. Pulse (or rub with your fingertips) until the mixture looks like fine breadcrumbs.

3. Bind the dough: Whisk the egg yolks with 1 tablespoon of ice water. Add it to the flour mixture and process just until the dough begins to clump together. If it’s too dry, add the second tablespoon of water.

4. Chill: Shape the dough into a smooth square disc, wrap it in plastic, and refrigerate for 30 minutes.

5. Roll and Line: On a lightly floured surface, roll the pastry out to about 3-4mm thickness. Carefully lift it and press it into your square pan, making sure it goes right into the corners and straight up the tall sides. Trim any overhang. Prick the base all over with a fork and freeze the lined pan for 15 minutes.

6. Blind Bake: Preheat your oven to 350°F (175°C). Line the pastry with parchment paper, fill it to the top with baking weights (or uncooked rice/beans), and bake for 15 minutes. Remove the weights and paper, then bake for another 10 minutes until the base is dry and lightly golden. Set aside to cool completely.

Step 2: Cook the Sliceable Custard Filling

1. Heat the milk: In a saucepan, heat the whole milk and vanilla over medium heat until it just begins to simmer. Remove from heat.

2. Whisk the base: In a medium bowl, vigorously whisk the 6 egg yolks, granulated sugar, and cornstarch together until pale and smooth.

3. Temper the eggs: To prevent scrambling, slowly drizzle about a cup of the hot milk into the egg mixture while whisking constantly.

4. Thicken on the stove: Pour the tempered egg mixture back into the saucepan with the remaining milk. Cook over medium-low heat, whisking continuously and energetically.

5. The Magic Step: As soon as it bubbles, it will suddenly become incredibly thick. Keep whisking on the heat for 1 full minute to cook out the floury taste of the cornstarch.

6. Finish: Remove from heat and stir in the 30g of butter until melted and glossy.

Step 3: Assemble, Set, and Slice

1. Fill the shell: While the custard is still warm, pour it directly into your cooled, baked shortcrust pastry shell. Smooth the top perfectly flat with a spatula (exactly like the smooth surface in the photo).

2. Prevent a skin: Press a sheet of plastic wrap directly onto the surface of the hot custard. Let it cool to room temperature.

3. Chill completely: Transfer the tart to the refrigerator and chill for at least 2 to 3 hours (or overnight). The custard must be cold to hold its structure.

4. Slice: Once fully set, gently remove it from the pan. Use a long, sharp knife dipped in hot water (and wiped dry) to slice it into perfect, clean squares.

💡 Pastry Chef Secret for Visual Perfection:

To get the gorgeous two-toned look in the photo, your shortcrust pastry edges should bake to a deep golden brown, while the custard center stays a clean, solid, pastel cream-yellow. If you notice your pastry edges browning too fast during step 1, loosely tent the edges with aluminum foil!