Mix the quark, sugar, lemon zest, eggs and custard powder until smooth. Fold in the tangerines or cherries from the glass. Pour the quark mixture into the mold and smooth it out.
Bake in a preheated oven (circulating air approx. 150 °) for 50-60 minutes.
Let the cake rest for 10 minutes with the oven door open. Then remove from the edge of the mold with a knife and let cool in the mold.
Roast the coconut flakes in a pan until golden brown and leave to cool. After cooling, take the cake out of the mold and sprinkle with the desiccated coconut and granulated sugar.