Fry the onions cut into rings in a little oil, then add the drained mushrooms and continue frying. Then cut the cooked ham and raw ham into small cubes and fry them for a few minutes. Mix the sour cream with the whipped cream and season with salt and pepper. Add the whole thing to the onion mixture and let cool down a little. Then put everything over the schnitzel in the baking dish and cover everything in the fridge for about 24 hours.
The next day, everything is placed in the preheated oven for approx. 60 minutes (top / bottom heat: 200 ° C, hot air: 180 ° C).
Baguette, rice, fried potatoes or gnocchi can be served as a side dish.