Wash carefully 1 lb. of tripe that has not been pickled, and cut into inch squares. Put it into a stew pan with ¼ teaspoon each of salt, sugar and prepared mustard, with water enough to cover, about 1 pint. Boil up and skim carefully, then set back to simmer for 3 hours, watching closely lest it stick to the bottom of the pan and skim if necessary. Mix a tablespoon flour with a little cold water, stir it in, simmer ½ hour longer, and serve with more seasoning, if desired.
Or, one hour before serving, cook 6 medium sized onions ½ hour. Drain and slice them, and put them into a dry frying pan with 2 tablespoons of fat. Season with 1 teaspoon each of salt, sugar, dry mustard, a little white pepper and nutmeg; cook until golden brown and pour over the tripe; thicken with the flour.