Core the apples and cut into small pieces. Put the lemon juice in a saucepan and simmer on medium heat for approx. 10-15 minutes until they are nice and musky, then let cool down well (of course, ready-made applesauce can also be used).
For the quark mixture, beat the sugar and vanilla sugar with the eggs until creamy. Add soft butter and then gradually add the quark. Carefully fold in the starch or pudding powder together with the applesauce or beat briefly with the hand mixer.
Put the mixture in a well-greased springform pan and bake in a preheated oven at 180 ° C top / bottom heat or 160 ° C fan oven for about 60 minutes. At the end of the baking time, let the cake rest in the slightly opened oven for 30 minutes and only then remove it.