Mix vanilla sugar, flour, sugar and almond kernels. Knead together with egg yolks and butter flakes to form a firm dough. Place in foil to cool for one hour.
Preheat stove to 175 °C
Line baking sheet with parchment paper. Roll out dough in batches 2 mm thin on floured surface. Cut out cookies (5 cm Â) with a round cutter with wavy edge. Cut three holes in the center of each half of the cookies with a round cookie cutter (1 cm Â). Place all the cookies on a baking sheet.
Bake in the middle of the oven for 10-12 minutes until golden brown (gas: level 2).
Cool on a cooling rack.
Heat the jelly while stirring. Brush the cookies without holes with it, press the remaining cookies on top. Dust with powdered sugar, put a little bit of jelly in the holes.