Cut the marzipan into pieces. Cream soft fat and marzipan pieces with the whisk of the hand mixer. Add sugar and eggs bit by bit. Keep stirring until the sugar is dissolved and the mixture is light and creamy. Add the butter-vanilla flavouring.
Mix flour and baking powder and stir in. Add enough milk so that the dough falls off the whisk. Cut the chocolate into pieces and fold them into the dough with a mixing spoon so that the chocolate pieces remain whole. Pour the sponge mixture into a well greased cake tin (1 1/2 litre capacity). Bake the cake in a preheated oven (electric: 175 °C/ gas: level 2) for 60-70 minutes. Let the cake cool down a bit and turn it onto a cake rack and let it cool down. Coarsely chop the chocolate coating and melt in a hot water bath. Place the cake rack on a piece of aluminium foil. (So you can still use the excess couverture later.) Cover the cake with the couverture evenly. Let it set.
Let the cake cool down a bit and turn it onto a cake rack and let it cool down. Coarsely chop the chocolate coating and melt in a hot water bath. Place the cake rack on a piece of aluminium foil. (So you can still use the excess couverture later.) Cover the cake with the couverture evenly. Let it set. Dust with icing sugar before serving. Results in about 14 pieces
Preparation time about 15 minutes. Baking time 60-70 minutes (waiting time approx. 2 hours)