Beat the softened butter with the sugar and vanilla sugar until frothy, add the egg and a pinch of salt and stir everything very thoroughly.
Mix the flour with the baking powder, almonds and oat flakes and stir into the butter mixture in portions.
Preheat the oven to 190 ° C.
Line a baking sheet with parchment paper and use two teaspoons to put small heaps of the dough on the baking sheet. Make sure that there is always a large gap between the dough, as the cookies diverge. For this reason, it is best not to place more than 12 cookies on the tray.
Bake the biscuits on the middle shelf of the oven for about 10 minutes on top / bottom heat. Let cool on a wire rack and dust with icing sugar.