2 1/2 (1 oz.) squares unsweetened chocolate
2 c. sifted confectioners' sugar
3 tbsp. hot water
1 egg
1/3 c. soft butter
1 tsp. vanilla

Melt chocolate in mixing bowl over hot water. Remove from heat. With electric mixer, blend in sugar and water. Beat in egg, then butter and vanilla. Frosting will be thin at this point, so place bowl in ice water; beat until of spreading consistency. Frosts tops and sides of two 9-inch layers.