Mix eggs and sugar in a bowl.
Add Greek yogurt and milk, then mix well.
Sift cake flour, baking powder, and cocoa powder into the bowl.
Gently fold with a spatula until the batter is evenly mixed.
Add chocolate chips and lightly fold them in.
Line a baking pan with parchment paper, then pour in the batter.
Bake in a preheated oven at 180°C for 20-25 minutes.
Let cool on a wire rack and cut into pieces.