Drain the mandarins on a sieve. The juice is not used.
Stir the butter until creamy. Gradually add sugar, lemon juice and eggs, followed by baking powder, semolina and pudding powder. Stir in the quark. Mix the mandarins into the batter.
Fill into a springform pan and bake at top / bottom heat 180 ° C, fan oven 160 ° C for approx. 1 hour.