Mix butter, sugar and vanilla sugar until thick and creamy. Add flour, salt and baking powder, then knead well.
Roll out the dough on a floured surface to about half a cm thick, cut out cookies.
Now preheat the oven to about 180 °C, grease the baking tray or cover it with parchment paper.
Place the cookies on the baking tray and prick them a few times with a fork. Bake for about 20 to 25 min, then let the cookies cool. Be careful – the cookies break very easily!