Joshs Chocolate Sauce

2 cups powdered sugar
1 can evaporated milk
cup butter
1 tsp. Vanilla
2/3 cup chocolate chips (I use milk chocolate)

Mix sugar, milk, chips, butter and vanilla. Bring slowly to a boil. Boil (softly) for 8 minutes. (NOTE: You can tell when you take it off the burner if it is getting slightly thick. If not, boil a little longer. )