In a saucepan, combine water, milk, a pinch of salt, sugar, and butter. Heat until the butter melts.

Add flour, stirring vigorously to prevent lumps. Set the mixture over low heat, stirring for 5 minutes until it forms a dough.

Let the dough cool slightly before adding 2.5 eggs, one at a time, ensuring the mixture is smooth and homogeneous.

Spread the dough evenly in a greased baking pan. Bake at 180°C (350°F) for 25-30 minutes until golden. Let it cool.

Whisk 2 eggs, sugar, and starch until smooth.

Heat 400 ml of milk in a saucepan and slowly add the egg mixture, stirring constantly until it thickens. Let the cream cool and then cover to prevent a skin from forming.

Whip 200 grams of cold cream with vanillin until stiff peaks form. Fold into the cooled cream mixture until smooth.

Cut the cooled pastry into smaller pieces or leave as a single large piece, depending on preference.

Spread the cream filling over the pastry. If you’ve cut it into pieces, you might want to layer them or roll them individually.

Place the rolls in the refrigerator for a few hours to set.

Decorate with powdered sugar or drizzle with melted chocolate before serving.