Preheat oven to 350°F (180°C).

Roll out the Marzipanrohmasse to a thickness of about 1/4 inch. Cut out small cubes. Add 36 of the cubes to a bowl and set aside - these will be used to decorate the muffins.

Add butter to a mixing bowl. Mix until the butter is creamy. Add sugar and vanilla sugar - continue to mix until butter has absorbed sugar. Add eggs one at a time - making sure each egg is absorbed by the butter/sugar mixture before adding the next.

In a separate mixing bowl, combine flour, cocoa, and baking powder. Add to butter mixture and mix in - drizzle in milk and mix in at the same time.

Using a spatula, fold in the marzipan cubes.

Prepare a muffin pan by either greasing it or by lining it with muffin liners. Fill the muffin cups equally with the dough. Using the 36 marzipan cubes that you had set aside, top each muffin with 3 marzipan cubes.

Bake muffins for 30 minutes. Remove from oven and allow to cool in muffin pan for an additional 10 minutes.