Sift cake flour and cocoa powder together.
In a bowl, mix milk, sugar, and yeast.
Add eggs and melted butter, then mix.
Add the dry ingredients and knead the dough.
Let the dough rise for 1 hour (first fermentation).
Add chocolate chips and knead again.
Shape the dough into a ball.
After a second rise for 30 minutes, bake in a preheated oven at 180°C for 15 minutes.