3 sq. unsweetened chocolate
2 c. confectioners' sugar
1 tsp. vanilla
1/3 c. hot milk
1/4 c. butter

Combine chocolate squares and butter in top of double boiler. Mix together confectioners' sugar, vanilla and milk. Beat on low until blended. Beat in chocolate mixture on high speed. Beat until thick enough to spread. More confectioners' sugar or milk may be added to achieve desired consistency.