Remove the gall carefully from about a pint of chicken livers, wash them well, drain, and slice them into small pieces. Place them in a sautoire with one ounce of butter, range the pan on the hot stove, then season with one pinch of salt and half a pinch of pepper; toss the contents gently for two minutes; then add a pinch of chopped parsley, one pinch of chervil, and three well-minced mushrooms, and moisten with half a pint of Madeira sauce (No. 185), and let cook for five minutes; make an omelet of twelve eggs, as for No. 450, and when ready to finish, pour the livers in the centre, reserving two tablespoonfuls of it for further action; close the sides up carefully, cook two seconds longer, then gently turn it on a hot dish, and, with a spoon, pour all the sauce around the omelet. Dress the livers that were reserved, at both ends of the omelet, equally divided, and serve.