1. Start with the buttercream by making a pudding. Add the cornstarch and sugar to a small bowl and mix with some of the milk until the cornstarch has dissolved completely. Add the rest of the milk and vanilla extract to a small pot and bring to a boil (stir constantly). As soon as the milk starts to bubble, add the cornstarch mixture and mix in until the pudding starts to thicken. Take off the heat, cover with a piece of plastic wrap and let cool down completely. Make sure the plastic sits directly on the surface of the pudding so you don’t get a pudding skin.

 

2. For the rum syrup add the water and sugar to a small saucepan and bring to a boil. When the sugar has dissolved completely, take off the heat and add the rum. Set aside to cool down.

 

3. Preheat the oven to 350°F (180°C). Grease three 6 inches (15cm) baking tins and line with baking parchment. Set aside.

 

4. Add the butter to a large bowl and mix until soft and smooth. Add the sugars and mix until light and fluffy. Add the eggs one after another and mix well in between. Add the vanilla extract and mix in. In a separate bowl mix the flour with baking powder, nutmeg, cinnamon, and salt. Add alternating with the Eierlikör to the bowl (about 3 batches) and mix until just combined. Do not overmix! Divide the batter between the prepared baking tins, smooth out the surface and bake for 25-30 minutes until golden brown. Insert a toothpick into the center of the cake – if it comes out clean, you can take the cakes out of the oven. Let the cake layers cool down in the baking tins for about 10-15 minutes, then remove from the tins and place on a wire rack. Use a wooden skewer and poke several holes into the cakes, then brush with the rum syrup and let the syrup dissolve in the cakes. Let cool down completely.

 

5. As soon as the pudding has cooled enough and the cakes are cooled, you can finish the buttercream. Add the softened butter and confectioners‘ sugar to a large bowl and mix on high speed until light and fluffy – the butter and pudding should have about the same temperature. Add the cooled pudding gradually with a spoon while mixing constantly until you get a nice and smooth buttercream.

 

6. To assemble the cake place the first cake layer on a serving plate. Place a good amount of buttercream on top and spread evenly. Place the second cake layer on top and repeat with the buttercream – finish with the last cake and coat the whole cake with a thin layer of buttercream (crumb coat). Place in the fridge for about 30 minutes.

 

7. While the cake is cooling, add the cocoa powder to the buttercream and mix until well combined. Coat the cooled cake with the chocolate buttercream, keep some for the decoration of the cake and fill into a piping bag with a star tip. Decorate the cake with the chocolate shards, the remaining buttercream and chocolate eggs. Cool for at least one more hour before serving.