For the dough, knead all the ingredients and form it into a roll 1-2 cm thick.
Cut small pieces of it, form them into balls and place them on a baking tray lined with baking paper. If you like, you can press a pattern on them with a fork. (Caution: Do not place the balls too close together. They will separate a little).
Bake in the preheated oven at 150 °C convection oven for about 15-20 minutes until the cookies are lightly light brown.
For the sugar layer, mix the powdered sugar and vanilla sugar in a bowl.
Roll the Butterhupferl in the vanilla-dusted sugar mixture while they are still warm.