2 (1 oz.) squares unsweetened chocolate
4 tbsp. butter
2-3 c. confectioners' sugar, sifted
1/4 c. evaporated milk or cream
1 tbsp. peanut butter

Melt chocolate squares and butter over low heat; add confectioners' sugar alternately with evaporated milk until smooth and creamy. Add peanut butter and mix well. Frost top and sides of cake.