Mince boiled potatoes. Add the flour, egg and salt to taste. 1 egg, 1 tablespoon of flour is needed for 0.5 kg of potato. Make a tortilla of the mass and put filling on it. The filling may be different: fried cabbage with onion or mushrooms, or roasted carrots with mushrooms.
Give the tortilla with meat a crescent shape, toss in flour and fry.
Serve with the sour cream and mushroom sauce.