Bittersweet Chocolate Truffle Cheesecake

Preheat oven to 350ºF.

Crust: Combine the crumbs and butter and press the mixture onto the bottom of a 9-inch springform pan. Refrigerate the crust while the filling is being prepared.

Filling: Beat the cream cheese with the sugar until blended and smooth. Beat in the eggs, one at a time; beat in the coffee (or liqueur), then the melted chocolate; blend in the sour cream. Pour the filling over the prepared crust, smoothing the top. Bake the cheesecake for 40 to 50 minutes or just until the center is barely set; cool it on a wire rack, then in the refrigerator overnight. Run a sharp knife around the cheesecake to loosen it from the rim; remove the rim.

Glaze: Save a few curls from the back of one of the squares of chocolate; reserve them for the garnish. Bring the whipping cream to a simmer over low heat; add the remaining chocolate and stir the mixture until smooth. Spoon the glaze over the prepared cheesecake and garnish it with the reserved curls.