Cream butter until very light. Gradually add the icing sugar and continue to cream until fluffy. Gradually add athe lemon extract. Beat the egg white until stiff and fold it into the butter and sugar mixture. Place in a small serving dish and chill until hard. Yields 1 1/4 cups sauce. VARIATIONS: Brandy Hard Sauce....Omit the egg white. Substitute 2 tbls. brandy for the lemon extract and proceed as for Hard sauce. You may also add 1 tsp. vanilla to this recipe if desired. Almond Sauce....This sauce is excellent with steamed Cranberry Pudding. Proceed as for Hard Sauce recipe, substituting 1/2 tsp. almond extract for the lemon extract and leaving in the egg white. From the book "Canadian Christmas Cooking" by Rose Murray