Preheat the oven to 180°C (356°F).
In a bowl, combine cake flour, baking powder, sugar, and salt.
Cut cold butter into small pieces and blend with a scraper as if cutting.
Add mascarpone cheese and milk, knead quickly until it forms a dough.
Roll out the dough to 2cm thickness and cut into triangles.
Place on a baking sheet lined with parchment paper.
Brush a little milk on the surface and bake for 20 minutes.