French Mustard
Work together (until smooth) three tablespoonfuls of mustard and one of sugar, then add one egg which has been beaten, one teacupful of good vinegar, putting in a small quantity at a time to prevent its being lumpy. Beat all together until very smooth; place on the stove and cook only a few moments, stirring all the time; as soon as it becomes cool add one tablespoonful of olive oil, which must be worked in very smooth.