Grease troughs of a box cake tin very well. Coarsely chop nuts and kernels. Roast in a pan without fat. Take out and let cool down. Caramelise 100 g sugar until golden yellow and remove from the heat.
First add 10 g butter and then cream. Mix in nuts and seeds. Distribute immediately into the bowls. Preheat the oven (electric cooker: 175 °C/circulating air: 150 °C/gas: see manufacturer).
Wash the lemon hot, dab dry and finely grate the peel. Squeeze the lemon. Wash apple, remove seeds and grate coarsely with peel. Mix with 1 tablespoon lemon juice.
Cream 100 g soft butter, lemon zest and 100 g sugar with the whisks of the mixer. Stir in the eggs one by one. Mix in apple and sour cream. Mix flour and baking powder, stir in briefly.
Spread the dough on the caramelised nuts in the hollows. Bake in a hot oven for 20-25 minutes.
Take the cakes out of the oven and loosen each edge with a knife. Immediately turn out onto a cake plate and let it cool down. Attention! Some caramel may flow out.