Preheat the oven to 180°C (356°F).
Combine flour, baking powder, sugar, and salt in a large bowl.
Add cold butter and break it up using your hands or a pastry cutter until crumbly.
Add milk and egg to form a dough.
Flatten the dough and cut it into triangles.
Place the pieces on a baking sheet lined with parchment paper.
Brush the tops lightly with milk.
Bake in the preheated oven at 180°C (356°F) for 18–20 minutes.