Roughly chop the chocolate coating. Melt butter and chocolate coating in a small pot at low heat while stirring. Roast the nuts in a pan without fat and chop coarsely. Mix the melted chocolate coating and eggs in a large bowl with the whisk of the hand mixer. Add 350 g sugar, vanillin sugar, salt, flour and baking powder and mix to a smooth dough. Fold in chopped nuts. Grease the fat pan of the oven and spread the dough evenly on top.
Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for 20-25 minutes. Remove from the oven and let it cool down on a cake rack. In the meantime, roughly chop the white chocolate. Melt the chocolate and coconut oil in a bowl on a hot water bath. Spoon the chocolate into strips and splashes on the cake and chill for 30-60 minutes until the chocolate is firm. Cut the cake into about 48 pieces
waiting time approx. 1 1/2 hours