Take four fine fresh sweet-breads; trim them nicely, split them open, and remove the gristle or pipe. Then lay the sweet-breads in warm water till all the blood is drawn out. Afterwards, put them into a saucepan, set them over the fire, and parboil them for a quarter of an hour. Then take them out, and lay them immediately in a pan of cold water.
Have ready a quart of fresh mushrooms; peel them, and remove the stalks. Spread out the mushrooms on a large flat dish, with the hollow side uppermost, and sprinkle them slightly with a little salt and pepper. Having divided each sweet-bread into four quarters, put them into a saucepan with the mushrooms, and add a large piece of the best fresh butter rolled in flour. Cover the pan closely, and set it over a clear fire that has no blaze. You must lift the saucepan by the handle, and shake it round hard, otherwise, the contents may burn at the bottom. Keep it closely covered all the time; for if the lid is removed, much of the mushroom-flavour may escape. Let them stew steadily for a quarter of an hour or more. Then take them up, and send them to table in a covered dish, either at breakfast or dinner. They will be found delicious. If the mushrooms are large, quarter them.