For the apple crumble cake, first prepare the batter. For this, cream butter and sugar until fluffy. Add the eggs and continue to beat. Gradually add the flour mixed with baking powder and the milk.
The dough should be hard to tear from the spoon. (use a little more or less milk if necessary). Peel the apples, remove the core and cut into thin slices.
Knead fine crumbles from the ingredients for the crumble with your hands. Pour the mixture into a flat baking pan lined with baking paper, spread the apple slices on top in a fan shape and then cover with the crumble.
Bake everything in the oven at 180°C for about 50 minutes. (Test with chopsticks) Preheating is not necessary.