Steam leek and onion in the warm butter for a few minutes. Add mushrooms and steam briefly. Add sour cream, briefly lightly roll, season and spread evenly in a baking dish.
Cut cheese into 2 slices per unit.
Roast meat in the hot clarified butter on both sides for about 2 min each, season with salt, bell pepper and paprika. Place on top of the steamed vegetables. Deglaze the roast stock with white wine, bring to a boil and pour over the meat. Put a slice of cheese on each cutlet.
Bake in a 220 °C hot oven for about 10 minutes.
Tip: Instead of clarified butter, you can also use butter in most cases.