Mix flour, cocoa powder, yeast, sugar, and salt in a bowl.
Add warm milk, butter, and eggs, then knead into a dough.
Cover and let the dough rise for the first proof.
Divide the dough and shape into balls.
Wrap each dough with chocolate inside.
Place the dough balls on a baking tray and allow for a second proof.
Brush the top with milk.
Bake in a preheated oven at 180°C for 15 minutes.