Chop mushrooms and chicken liver, add the bigger part of butter, stir up. Add eggs, forcemeat, a dash of nutmeg, salt, pepper, pour cognac and stir well up.
Rub chicken with salt inside and outside, fill in with prepared mixture and sew. Sprinkle with oil.
Fry the chicken in oven, adding a dollop of water in baking sheet. When chicken gets golden, rub it with lemon juice, the remaining butter and fry until done, pouring with exuding juice from time to time.