For the batter, beat the margarine or butter until creamy. Stir in sugar, vanilla sugar and a pinch of salt. Gradually stir in the eggs and add the vanilla flavor. Mix the flour with the cornstarch and baking powder and stir in alternately with the milk.
Mix all ingredients together for the nut filling.
Grease a bundt pan (I used a 23 cm pan) and dust it with flour. Pour in the batter and spread the nut mixture on top. Now use a fork to spiral through the dough and nut mixture. Bake in a preheated oven at 180 ° C for 60 minutes.
Take the cake out of the mold and let it cool down. Then mix the ingredients for the topping and coat the cake with them.