Briefly heat the marzipan and butter in the microwave and then stir in the food processor to a smooth mass. Gradually add the sugar, the amaretto and the whole eggs.
Mix the flour and baking powder, sieve, then mix with the oatmeal in a large bowl. Puree the pineapple in a tall vessel with a hand blender. Fold into the dough together with the flour mixture using a fork. Finally add candied pineapple.
Grease a Guglhupfform with butter, then sprinkle with whole cane sugar (this gives the cake a particularly crispy crust). Pour in the dough and bake in the preheated oven to 175 ° C (convection) for about 60-70 minutes.
Take the cake out of the tin and let it cool down. Dust with powdered sugar or sprinkle with grated coconut flakes.