For the bottom, crumble the shortbread biscuits into tiny pieces in a bag. Melt the couverture over a water bath. Add the liquid chocolate to the shortbread and stir well. Then add the cocoa powder and stir well again. Distribute the mixture for the base evenly over 12 muffin pans, ideally in a silicone mold.
For the topping, put the sugar, cream quark, egg, custard powder and eggnog together in a bowl and mix well with a mixer or whisk. Spread the mixture evenly over the biscuit base. It opens a little bit, so don`t fill the hollows up to the brim.
Bake the muffins at 160 degrees air circulation for about 15-18 minutes. The curd mass must be firm.
Important: Only take the little cakes out when they have completely cooled down. If you like, you can decorate the cakes.