Melt the butter and pour over the oatmeal. Add flour, sugar, baking powder, vanilla sugar and stir. Depending on the consistency, use 1-2 eggs to smooth out the dough again. Place small heaps (approx. 1 1/2 tablespoons in size) on a baking tray lined with baking paper and bake at 180 degrees for 10-15 minutes until golden.
They taste best if you let them steep for a few more days.