Sauce Robert
Peel five large onions, and parboil them to take off some of the strength. Cut them into small dice, and put them into a stew-pan with a quarter of a pound of fresh butter, divided into four, and dredged with flour. When they are well browned, pour on them half a pint of beef or veal gravy, and let it simmer for a quarter of an hour. Season it slightly with cayenne. Just before it goes to table, stir in a table-spoonful of French mustard.
This is a good sauce for any sort of roast meat, or poultry.