Step #1 mix the chocolate & butter & melt over very low heat, stirring until mixd.
Step #2 mix in the confectioners sugar & salt alternately with the milk & vanilla, mixing until the frosting is smooth and has a good consistency for spreading.
Step #3 To give the frosting extra gloss & richness, add 1 egg yolk along with the milk.
Step #4 For extra flavor, rum, substitute 1 1/2 Tbsp of strong coffee, or brandy for part of the milk.
Step #5 YIELD: Frosting for two 8-inch or 9-inch layers or a 9- x 13-inch cake.