Sauce Robert.—Cut two medium sized onions into dice, and fry in butter till of a golden brown, then drain off the butter, and cook them in a little stock with a tiny pinch of sugar, till melted; meantime boil a full half pint of espagnole with a gill of light French wine (or white wine vinegar), and a handful of mushroom stalks and trimmings, till reduced a fourth part; sieve it, stir it to the onions, add a good spoonful of made mustard and serve. Excellent with pork cutlets, hashed goose, etc.