Wash the meat and pat dry well. Peel the onion and chop finely. Drain the mushrooms, halve or quarter if necessary. Cut the pickled cucumber into small slices.
Heat the oil and fry the meat in it, add onions and mushrooms and fry for about 5 minutes. Dust with 1 tablespoon flour, sweat and deglaze with cream. Add the pickles and simmer for another 5 minutes. Season with salt and pepper and stir in the mustard.
Peel, wash and roughly grate the potatoes. Boil in salted water for 3 - 4 minutes, drain. Put the strips in a baking dish. Mix the potatoes with the egg and flour. Season with salt and pepper.
Spread the potato mixture over the strips. Bake everything in the preheated oven at 175 ° C for approx. 40 minutes. A mixed salad tastes good with it.