Step #1 Melt chocolate & butter in a double boiler; cool to room temperature.
Step #2 Mix the powdered sugar, whipping cream, & vanilla until well mixed.
Step #3 stir in the the melted chocolate.
Step #4 If necessary, let the frosting sit until thick enough to spread with a knife (should only need to let it set if your chocolate was still warm).
Step #5 This frosting is very rich & tastes like fudge! Enjoy.