Beat the egg whites with the mixer until stiff. Little by little, briefly omit sugar, vanilla sugar and flavor. Carefully stir in the hazelnuts on the lowest setting.
Place 2 teaspoons of dough in piles on a baking sheet lined with baking paper, leaving enough space between the piles of dough. Use a wooden spoon handle to make a small indentation in each of the dough.
Put the baking trays one after the other for 15 minutes at 180 ° C.
Take the cookies from the tray. Pour some jam into the hollows of the hot cookies.
Tip:
The biscuits also taste really delicious without jam.