Sauce for Lobsters.
5 tablespoonfuls fresh butter.
Teacupful vinegar.
Salt and pepper to taste, with a heaping teaspoonful white sugar.
1 teaspoonful made mustard.
Minced parsley.
Beat the butter to a cream, adding gradually the vinegar, salt, and pepper. Boil a bunch of parsley five minutes, chop small; beat into the butter; lastly the sugar and mustard. The butter must be light as whipped egg.