Beat the egg white with a pinch of salt until it is semi-stiff, whip in the sugar and vanilla sugar, gradually add the yolks and whip everything until frothy. Fold in the flour and spread the dough on a baking sheet lined with baking paper. Bake at 180 degrees in the preheated oven on the middle rack for 15 minutes until golden brown.
Overturn on baking paper sprinkled with granulated sugar, fill as desired and roll up.
As a variant, 100 g of the flour can be replaced with nuts or grated pumpkin seeds.