This is one IMPRESSIVE dessert that is immensely delicious. If you love cheesecake and are "mad" about chocolate, this is a little treasure you will use often. It is a dense filling, so please don't overbeat. You do not want too much air incorporated in the filling. Just beat until blended, no more.I can't tell you how many times I've made this, and if there are any leftovers, it freezes divinely. From Denny Darling.
In a 10" springform pan, spread the butter on the bottom and sprinkle crumbs evenly over all. Set pan aside.
In the large bowl of an electric mixer, beat together cream cheese, sour cream, eggs, sugar and vanilla until blended.Do not overbeat. Beat in the melted chocolate until blended. Pour mixture into prepared pan and bake at 350 for 45 minutes. Allow to cool and then refrigerate for at least 6 hours. Overnight is good, too.
Decorate top with a generous sprinkle of grated chocolate. To serve, cut into wedges and keep the portions small. Serves 12
Note: Can be prepared 1 day earlier and store in the refrigerator. Two tablespoons of Crème de Cacao can be added to the cream cheese mixture, if you enjoy the subtle addition of liqueur.
Source: My Old Recipes
Note: I make this cheesecake often, and it always gets rave reviews. I've frozen the leftovers (if there are any) to treat myself to a great frozen dessert. L.