Peel and wash the potatoes and cut them into slices of about 2 mm thickness with a kitchen slicer or knife. Grease 2 small flat casseroles. Put potato slices in 2-3 layers like roof tiles.
Season each layer with salt and pepper and sprinkle with 1 tablespoon of cream. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for approx. 25 minutes. Wash the meat, pat dry and season with salt and pepper.
Heat the oil in a small ovenproof pan. Fry the meat for approx. 5 minutes, turning it well. For the crust, wash the apple, remove the core and dice the fruit. Mix butter and breadcrumbs.
Season with salt. Stir in the apple. Spread the crust on the meat and bake in the oven for about 5 minutes. Take the meat out of the oven, let it rest for a while and keep it warm. Wash parsley, shake dry, pluck leaves from the stalks and chop.
Arrange meat and gratin on plates, sprinkle with parsley and garnish with apple slices.