Mustard Sauce
["1/2 c. sugar", "2 Tbsp. flour", "2 Tbsp. butter", "1/2 c. vinegar", "1/2 c. mustard"]
["Mix sugar and flour.", "Add vinegar and mustard.", "Cook in double boiler until thick.", "Add butter."]
["sugar", "flour", "butter", "vinegar", "mustard"]