Chocolate Cream Profiteroles

For the cream, whisk together egg yolks, sugar, vanilla sugar, cocoa powder, and flour in a saucepan. Pour in the milk and cook over medium heat until thickened, stirring constantly, then stir in the butter until fully incorporated and chill in the refrigerator to set.

Combine water, milk, salt, sugar, and butter, bringing it to a boil over medium heat. Once boiling, remove from the heat, add the sifted flour, and stir vigorously with a spatula for 2-3 minutes. Let the mixture cool slightly, then beat in the eggs. Pipe rounds onto parchment paper, snip off any pointy tips with scissors, and bake in the oven at 180°C (350°F) for 30 minutes.