Mix the flour, powdered sugar and vanilla sugar evenly, add the margarine and knead everything vigorously. Then let everything rest in the refrigerator for about an hour.
After cooling, roll a thick sausage out of the dough and cut into even slices. Spread the resulting biscuits on baking trays and bake for about 20 minutes at 180 ° C. The biscuits don`t have to get too brown because they taste best!
If you like, you can also decorate the biscuits with chocolate or simply dust them with powdered sugar.