Preheat the oven to 180°C (356°F).
In a bowl, mix cake flour, cocoa powder, baking powder, sugar, and salt.
Cut cold butter into small pieces and rub it in with your hands until evenly combined.
Add milk and egg, then gently bring the dough together into one mass.
Fold in the chocolate chips and mix evenly.
Roll out the dough thickly and cut into triangle shapes.
Arrange the scones with some space on a baking sheet lined with parchment paper.
Bake in the oven at 180°C (356°F) for 20–25 minutes.