Put the first seven ingredients in a bowl and make a batter. Place on a baking tray lined with baking paper and distribute evenly.
Bake in the preheated oven at 160 ° C (top / bottom heat: 175 ° C) on the lower rack for approx. 20 - 25 minutes.
Then let the cake cool down.
Spread the well-drained mandarins on the finished dough. Whip the cream with the cream stabilizer. Mix the sour cream with sugar and fold in the cream. Put the sour cream on the cooled cake. If necessary, apply a wave pattern with a serrated dough scraper or fork, then put cocoa powder in a hair sieve and sprinkle over it or alternatively put chocolate shavings over it.
Tips: You can use cherries instead of tangerines.
The sour cream mass can also be modified: Instead of sugar, you add C-fresh to taste or another orange beverage powder (also tastes great) and rub Ritter Sport (white and brown chocolate - available in a bar) over it.