Knead flour, curd and butter into a dough. Let the dough rest for 1/2 hour.
Then roll out the dough to the thickness of the back of a knife and cut out squares.
Place a teaspoon of jam on each square and fold into triangles. Press the triangles firmly together.
Brush with yolk and bake in a preheated oven at 180 °C for about 25 minutes.
Sprinkle the puff pastry with powdered sugar while still hot.