Ingredients:

For the Dough:

150g all-purpose flour
30g butter, chilled and diced
60g cold water
6g sugar
2g salt
70g butter, softened (for coating)

For the Filling:

4 egg yolks
85g sugar
10g corn starch
200g whipping cream
150g milk
3g vanilla extract

Instructions:

Make the Dough:

In a bowl, mix the flour, sugar, and salt. Add the chilled diced butter and rub it into the flour mixture until it resembles coarse breadcrumbs.
Gradually add cold water and mix until a dough forms.

Do not overwork the dough.
Wrap the dough in plastic wrap and chill in the refrigerator for 30 minutes.
Roll and Coat the Dough:

On a lightly floured surface, roll out the dough into a rectangle.

Spread the softened butter (70g) evenly over two-thirds of the dough.
Fold the unbuttered third of the dough over the middle third, then fold the remaining third over the top (like folding a letter).
Rotate the dough 90 degrees, roll it out again into a rectangle, and fold it in the same way.

Chill in the refrigerator for another 30 minutes.
Prepare the Filling:

In a bowl, whisk together the egg yolks, sugar, and corn starch until smooth.
In a saucepan, heat the whipping cream, milk, and vanilla extract until just below boiling.

Gradually pour the hot cream mixture into the egg yolk mixture, whisking constantly.
Return the mixture to the saucepan and cook over low heat, stirring constantly, until thickened. Remove from heat and let it cool.
Assemble and Bake:

Preheat the oven to 220°C (428°F).
Roll out the dough thinly and cut out circles to fit into a muffin tin. Press the dough circles into the muffin cups.
Fill each cup with the custard filling.
Bake for 20-25 minutes, or until the pastry is golden and the custard is slightly caramelized on top.
Serve:

Let the tarts cool in the pan for a few minutes before transferring them to a wire rack to cool completely.
Enjoy your crispy Portuguese Custard Tarts!