Preheat the oven to 180°C (356°F).
Mix whole wheat flour, baking powder, and salt in a bowl.
Add cold butter and rub with your fingertips until the mixture becomes crumbly.
Add milk, sugar, and egg, then knead into a single lump of dough.
Roll out the dough to 2–3 cm thickness and cut into rounds.
Place on a baking tray lined with parchment paper.
Bake in the oven at 180°C for 20–25 minutes.
Transfer to a cooling rack to cool.