Fricasseed snapping turtle

Have your fish merchant clean your turtle after he has killed him by throwing him into boiling water. Cut the turtle into neat dice, sprinkle with salt, pepper, onion juice, a dash of kitchen bouquet and a tablespoonful of mushroom catsup. Turn into a saucepan, add just enough cold water to cover the meat, fit a top on the vessel and simmer for half an hour. Now add a tablespoonful of browned flour rubbed to a paste with a great spoonful of butter; when this is blended with the liquid in the pan, add a glass of sherry and stir in very gradually the beaten yolk of an egg. Bring to the boil and remove from the fire. Turn into a deep heated dish.