Mix the oil with the sugar and vanilla sugar until frothy. Add the eggs and beat until creamy. Mix the flour with the hazelnuts, the baking powder and the pulp of half a vanilla pod and stir into the egg mixture. Add the egg liqueur and mix everything well.
Butter 12 small bundt cake molds and sprinkle with breadcrumbs. Pour in the dough and bake in a preheated oven at 180 ° C for about 25 minutes.