Peel the apples or pears and cut into small pieces. Soak them in rum or schnapps for at least 2 hours. Preheat the oven to 190 degrees.
Beat the butter until frothy. Then gradually stir in the sugar, chocolate and eggs. Mix the flour, hazelnuts, cocoa, cinnamon, baking powder and clove powder together in a separate bowl. Then mix the butter sugar mixture with the flour mixture and quickly mix in the apples. Everything should go very quickly in order to get the muffins into the oven quickly so that they are nice and juicy and rise well! Baking time: approx. 15 minutes.
The finished muffins can be decorated with powdered sugar.