Melt coconut oil in a pot and let it cool down. Sieve the icing sugar and cocoa into a bowl, add vanillin sugar and mix everything. Gradually stir in eggs, lukewarm fat and liqueur with the whisk of the hand mixer. Line a box form (approx. 25 x 10 cm; 1 1/4 litre capacity) with baking paper. Possibly put 1 biscuit aside for decoration. Place one layer of biscuits side by side on the bottom of the mould and spread about 1/4 of the chocolate mixture on top.
Lay 3 more layers of biscuits and chocolate mass alternately on top of each other. Finish with a layer of chocolate. Chill for at least 4 hours, preferably overnight. Turn the cake out of the tin and remove the baking paper. Decorate the cake with orange peel, mint and biscuit. Serve with ice cream