Peel and wash the potatoes and cut them in half lengthwise. Heat 2 tablespoons of oil in a frying pan. Fry the potatoes for about 20 minutes. Season with salt and pepper
Wash the fillets and pat them dry. Heat 1-2 tablespoons of oil in a large frying pan. Brown the fillets in it all around, season. Place beef fillet on a baking tray and roast in a preheated oven (electric cooker: 200 °C/circulating air: 175 °C/gas: level 3) for approx. 20 minutes, pork fillet for approx. 15 minutes
In the meantime, cover the beans and cook them in boiling salted water for about 15 minutes. Clean, wash and halve the mushrooms. Add them to the potatoes about 5 minutes before the end of the frying time and fry them. Season to taste
Drain the beans. Put them in a large greased casserole dish with potatoes and mushrooms. Cut the fillets into slices and place on top. Cut the cheese into small pieces and spread over it. Bake in the oven at the same temperature for about 10 minutes