Preparation:
Preheat the oven to 200°C.
In a large bowl, mix the flour, sugar, baking powder and salt.
Add the cold butter and mix with your fingertips or a dough mixer until it reaches a sandy consistency.
Add the cold milk little by little until you obtain a soft but non-sticky dough.
Roll out the dough on a lightly floured surface to a thickness of 1-1.5 cm.
Sprinkle ham and cheese on half of the dough, cover with the other half and gently press together again.
Cut out circles with a glass or cookie cutter.
Brush with egg yolk and sprinkle with sesame or black cumin seeds if desired.
Bake in preheated oven for 15-18 minutes until golden brown.
Serve warm.
