Slice a tender piece of beef into thin cutlets and pound them thoroughly. Sprinkle with salt and pepper and set aside for ½ hour. Fry 2 finely chopped onions in butter, mix with grated rye bread or a roll, and add salt, pepper, nutmeg, 4–8 chopped, boiled boletus or field mushrooms, and 1 egg. Mix together, spread some of this stuffing on each cutlet, and roll up into a tube (if you do not have the knack of rolling them neatly, tie each one with string). Sprinkle with flour and place them in a stewpan with rendered kidney fat or melted butter. Stew, covered, over a low flame. When they have browned on all sides, pour in about 2 glasses of bouillon. If the sauce boils away, then add some more.
One glass sour cream, a little mushroom bouillon, and a handful of grated rye bread crumbs may be added to this bouillon. Bring to a boil and pour over the cutlets on the platter. The cutlets should stew for a total of 45 minutes.