Add the swollen oatmeal, onion and grated eggs to the mushrooms. Mix everything well into a homogeneous mass. Add salt and seasonings. Add starch to the mass and mix well again. If the mass is watery, add another half-spoonful of starch.
This time I didn't add eggs, because I was preparing a lean version. Pour the flour onto a wide, flat plate. Shape the cutlets with wet hands, roll well in flour and fry over medium heat until golden brown.