Melt 6 squares unsweetened chocolate. Beat 3 egg yolks until thick add 1 1/4 cup sugar, 3/4 cup milk and 1 1/2 tablespoons butter. Cook in a heavy sauce pan over very low direct heat, stirring constantly. (Watch and stir). Bring to a boil. Boil 1 min. Remove from heat stir in the melted chocolate a pinch of salt and 2 teaspoons vanilla. Beat until it will spread nicely. Put the layers together with a good layer of icing, then frost the sides and top of the cake. This chocolate frosting has a gloss stays soft and doesn’t run.
(Handwritten in pencil on small piece of paper)
I remember this frosting and the cakes were always beautiful. I've used it a few times and I love the way the cakes look.