For the shortcrust pastry, pile the flour on the work surface and make a well in the middle. Add sugar, salt and an egg, distribute the cold butter in flakes around the edge. Knead all ingredients quickly to form a smooth dough. Then wrap the dough in foil, flatten it a little and refrigerate for 30 minutes.
Grease the springform pan. Roll out the shortcrust pastry on a little flour, slightly larger than the form and place in the form, pulling up one edge. Chill the dough base for around 10 minutes.
Preheat the oven to 160 ° C fan oven.
For the cream, cut the marzipan into small pieces. Beat the soft butter with a hand mixer until frothy. Add the marzipan and sugar and stir until it is smooth. Now stir in one egg after the other, add the lemon peel and flour and work in briefly.
For the topping, peel and halve the apples, cut out the core and cut the halves in a fan shape on the round side.
Spread the marzipan cream evenly on the shortcrust pastry and cover with the apple halves. Melt 25 g butter in a saucepan and brush the apples with it.
Bake the cake in the lower third of the oven for about 45 minutes until golden brown. Take out and let cool on a wire rack.