Quickly knead flour, sugar, vanilla sugar, yolks and butter into a dough and let rest in the refrigerator for 1-2 hours.
Then roll out 2-3 mm thick, cut out cookies with a round mold and place them on a baking tray lined with baking paper.
Poke a hole in the center of half the number of cookies. Bake in a preheated oven at 175 °C for about 13 minutes. Allow to cool.
Sugar the cookies with the hole with powdered sugar and put them together with a cookie with currant jam without a hole.