Mix the butter with the sifted sugar, vanilla sugar, rum, vanilla flavor, orange flavor, cinnamon and nut nougat until frothy. Gradually stir in the egg yolks, mix the flour with the baking powder, sieve and stir into the yolk mixture with the coarsely ground speculoos biscuits and natural yoghurt. Add walnuts with aranzini.
Beat egg whites into snow and fold in.
Dust the chilled, diced marzipan with a little flour and mix with the dough.
Pour the dough into a greased, floured Gugelhupf pan and bake in the preheated oven for a good 60 minutes at 180 ° C.
Let the Gugelhupf cool down and decorate as desired