Preheat the oven to around 190 ° C (top / bottom heat). Mix the butter and sugar together well. Add the flour and stir in well. Add the vanilla sugar and the potato chip crumbs (yes, actually salted chips. Don`t be deterred) and work in.
Put two teaspoons on a baking sheet lined with baking paper. Leave some space in between. Flatten it a little if necessary.
Bake for 15-20 minutes. Remove from oven and allow to cool.