Microwave Fudge
["1/2 c. margarine or butter", "2 c. sugar", "1 (5 oz.) can (2/3 c.) evaporated milk", "2 c. tiny marshmallows", "1 (6 oz.) pkg. (1 c.) semi-sweet chocolate pieces *", "1/2 tsp. vanilla", "1/2 c. nuts (optional)"]
["*Butterscotch or peanut butter flavored pieces can be substituted for chocolate."]
["margarine", "sugar", "milk", "marshmallows", "semi-sweet chocolate", "vanilla", "nuts"]