Favorite Soft White Frosting
["5 Tbsp. flour", "1 c. milk", "1 c. sugar", "1/2 c. shortening", "1/2 c. margarine", "1 Tbsp. vanilla"]
["Mix flour and milk; heat slowly until it makes a thick paste. Cool in refrigerator.", "Combine remaining ingredients; beat until fluffy.", "Add flour paste and beat well."]
["flour", "milk", "sugar", "shortening", "margarine", "vanilla"]