Boil, blanch, cool, and chop very fine two sweetbreads ; mix with them one-half their bulk of fine crumbs, previously soaked and rubbed smooth with a little cream. Beat up the yolk of a raw egg, and work all with pepper and salt to a paste. Make into small balls with floured hands, and set by for half an hour in a cold place. Strain off a quart of soup from your stock jar, when you have skimmed it. Heat and boil slowly five minutes, skimming it well. Drop in the balls carefully - not to break them; simmer ten minutes gently, and pour into the tureen.