In a medium pot, combine one cup of water and one cup of butter over medium heat. Stir until the butter melts completely.

Once boiling, remove the pot from heat and add flour all at once. Stir vigorously until the mixture forms a ball that pulls away from the sides of the pot.

Allow the dough to cool slightly before adding the eggs one at a time, mixing well after each addition. Your dough should be glossy and smooth.

Divide the dough in half. Spread the first half onto a greased baking sheet.

Bake in a preheated oven at 400°F (200°C) for about 25-30 minutes or until golden brown. Remove and let it cool completely before repeating with the second half.

In a saucepan, combine the milk and sugar, and heat until warm.

In a bowl, mix cornstarch with a little cold milk to make a slurry. When the milk is warm, whisk in the cornstarch mixture.

Bring it to a gentle boil, stirring until it thickens. Remove from heat and stir in vanilla extract. Let cool.

Once the pastry layers and cream filling are cool, spread the cream evenly over one baked layer.

Carefully place the other baked layer on top.

Dust the top with powdered sugar and let it chill in the refrigerator for a few hours before serving.