Heat the water and butter in a saucepan until the butter is completely melted and the mixture boils.

Add the flour at once and stir vigorously with a spatula until the mixture forms a cohesive ball and separates from the pan.

Let the batter cool for 5 minutes, then add the eggs one at a time. Mix well after each addition until the batter is smooth and glossy.

Put the batter in a piping bag and pipe small mounds onto a baking sheet lined with baking paper.

Mix the butter, sugar, flour, and a pinch of salt in a mixing bowl to form a crumbly dough.

Roll out the dough thinly between two sheets of baking paper and let it set in the refrigerator for about 15 minutes.

Cut small rounds from the dough and place them on top of the piped-on puffs.

Preheat the oven to 200°C. Bake the puffs for 20-25 minutes until nicely risen and golden brown. Do not open the oven during baking to prevent collapse.

Let the puffs cool completely on a wire rack.

Pastry cream: Bring the milk together with the vanilla pod (cut in half and the seeds scraped out) to a boil. Meanwhile, mix the sugar, egg yolks, and cornstarch until smooth. Pour a little of the warm milk into the egg mixture and stir well. Pour this mixture back with the rest of the milk and heat over medium heat while stirring constantly, until the mixture thickens. Let cool with a sheet of plastic wrap directly on top of the cream to prevent skin formation.

Crème Prise: Mix the cooled pastry cream with the whipped cream to form an airy cream.

Fill a piping bag with the cream prise and fill the cooled puffs by making a small hole in the bottom.