For the dough, beat the egg and yolk with the hand mixer with the whisk on the highest setting until frothy. Mix the sugar with the vanilla sugar and clove powder and gradually stir in. Stir in the aroma. Mix flour with baking powder, stir in seven and half of it on the lowest setting. Knead in the remaining flour on the floured work surface with your hands.
Shape the dough into small balls about 2 cm in diameter and place them on a baking sheet lined with baking paper. Press a hazelnut in the middle of each ball of dough.
Bake in the preheated oven at 180 ° C for about 10 minutes. The pastries should stay light. After cooling, pack the cookies airtight.