Grease a box form (approx. 30 cm long; 2 l capacity) and sprinkle with breadcrumbs. Cream butter, sugar, vanillin sugar and salt. Stir in the eggs one by one. Mix flour and baking powder, alternating with the milk, and stir briefly into the mixture in portions
Spread 1/3 of the dough into the mould. Spread half the confectionery on top. Spread 1/3 of the dough on top. Spread the rest of the confectionery and then the rest of the dough. Bake in the preheated oven (electric oven: 175 °C/circulating air: 150 °C/gas: level 2) for about 1 hour. Let them cool down
Roughly chop the chocolate coatings. Melt the dark chocolate coating in a hot water bath. Cover the top of the cake with it. Let it dry a little. Melt the milk chocolate coating and pour it in strips. Let it dry.