Dark Chocolate Frosting by Martha Stewart

1 pound semisweet chocolate (the good kind)
6 tablespoons cocoa
6 tablespoons boiling water
1 1/2 sticks unsalted butter
1/2 cup powdered sugar
dash of salt

Put chocolate in a heat proof bowl. Place over a pot of simmering water on the stove. Turn the heat off. Let the chocolate melt, stirring every so often, for 15 minutes. Remove bowl from the pot and let the chocolate cool for 30 minutes.
Combine cocoa and water, stir to dissolve cocoa.
Beat butter, sugar and salt until light and fluffy, about 3 or 4 minutes. Add melted chocolate and beat for 1 or 2 minutes. Add cocoa mixture and beat to combine.

I made this cake for Jason's birthday yesterday. This frosting is totally worth the effort, especially if you like dark chocolate, which I do!