Beat the egg whites until stiff, add 2/3 of the sugar and beat a little more.
Mix the soft butter with the soft, finely chopped marzipan, the remaining powdered sugar and the vanilla sugar until creamy, gradually stir in the egg yolks. Stir in the flour mixed with baking powder and starch with 25 ml of amaretto, then fold in the egg whites.
Pour half of the dough into a well-greased Gugelhupf tin, sprinkled with breadcrumbs. Stir the cocoa powder and the remaining amaretto into the remaining dough, pour the dough onto the light dough in the form and smooth it out.
Bake the cake in a preheated oven at 160 ° for about 45 minutes (stick test). Sprinkle the cooled cake with powdered sugar.