Belgian Mattentaart (Matzentaart)

Step 1

Set the oven to 400°F and wait until it finishes heating, about 10 minutes.

Step 2

Remove the pastry from the fridge and fit it into a 9-inch tart pan or pie dish, pressing gently into the corners and up the sides until it covers the bottom and edges completely.

Step 3

Prick the pastry all over with a fork to prevent it from puffing up unevenly, making 8–10 small holes across the entire surface.

Step 4

Pour 1.5 cups of milk into a small saucepan and set it over medium heat until steam rises from the surface and small bubbles appear at the edges, about 3–4 minutes.

Step 5

In a medium bowl, whisk together the 4 egg yolks and 0.33 cup sugar until the mixture turns pale yellow and thick, about 2 minutes of continuous whisking.

Step 6

Sprinkle the 2 tablespoons of cornstarch over the egg mixture and whisk until no lumps remain and the mixture looks smooth and uniform.

Step 7

Slowly pour the hot milk into the egg mixture while whisking constantly to avoid scrambling the eggs—this should take about 1 minute of continuous pouring and whisking.

Step 8

Pour the combined mixture back into the saucepan and set it over medium heat, whisking constantly until it thickens into a custard the consistency of thick pudding, about 3–5 minutes.

Step 9

Remove from heat and stir in the 1 teaspoon of vanilla extract and the optional cinnamon until fully blended.

Step 10

Pour the warm custard into the pastry-lined pan and spread it evenly with a rubber spatula until it reaches the rim, creating a smooth, level surface.

Step 11

Place the tart in the preheated oven and bake until the pastry edges turn golden brown and the custard surface looks set but with a slight jiggle in the very center, about 20–25 minutes.

Step 12

Remove from the oven and let cool on a wire rack for at least 15 minutes before slicing, allowing the custard to set completely.