1/2 c. butter
1/2 c. Crisco
1 c. sugar
2 tsp. vanilla
2/3 c. Pet milk (5 1/3 oz. can)

Make sure butter and Crisco are room temperature, then put all ingredients together and beat for about 30 minutes constantly. It may look sort of curdled but the last 10 minutes it becomes creamy and tastes out of this world.