1/2 c. sugar
1 1/2 tbsp. cornstarch
1 oz. chocolate (unsweetened), grated
Dash salt
1/2 c. boiling water
1 1/2 tbsp. butter
1/2 tsp. vanilla

Mix sugar, cornstarch; add chocolate and salt. Add water; cook until mixture thickens. Remove from heat; add butter and vanilla. Spread on cake while hot. Will frost 1 loaf cake or 1 (9-inch) square cake.