To make the crust, preheat the oven to 400? F. Line the bottom of a 9-inch springform pan with a round of parchment paper. In a medium bowl combine the cookie crumbs, sugar, and melted butter. Stir with a fork until all the crumbs are moistened. Add the crumb mixture to the springform pan and gently press about 1 inch up the sides of the pan. Press the rest of the crumbs into an even layer over the bottom of the pan. Bake for 10 minutes, then transfer to a wire rack to cool. Reduce the oven temperature to 300? F.

To make the filling, combine the sour cream, vanilla, and espresso powder in a small bowl. Whisk to blend and set aside. Melt the chocolate in a double boiler or in the microwave (in short intervals, stirring frequently) until completely smooth. Set aside and let cool slightly.

In the bowl of an electric mixer, combine the cream cheese, cocoa powder, and salt. Beat on medium-high speed until smooth and fluffy, about 2 minutes. Beat in the sugar and continue mixing about 2-3 minutes more, scraping down the bowl as needed. Add the cooled chocolate to the bowl and mix on medium-low speed. Beat in the sour cream mixture just until evenly blended. Beat in the eggs one at a time, mixing each just until incorporated. (Don’t over-beat once the eggs are added or the cheesecake will puff too much.)

Pour the filling into the cooled crust. Bake until the center jiggles very slightly when nudged, about 50-60 minutes. Transfer to a wire rack to cool for 1-2 hours. Then cover and refrigerate until thoroughly chilled, at least 8 hours or overnight. (In my opinion, the greatest disservice you can do your cheesecake is not chilling it long enough. Always let it chill completely through. I promise, it will be worth the wait!)

To make the glaze, place the chopped chocolate in a small heatproof bowl. Bring the cream to a simmer in a small saucepan or in the microwave. Pour over the chocolate and let stand briefly, 1-2 minutes. Whisk just until a smooth ganache has formed. Whisk in the butter until completely incorporated. Pour the glaze in an even layer over the chilled cheesecake. Chill thoroughly.

To serve, carefully unmold the sides of the springform. Run a sharp knife under hot water to warm the blade, and wipe dry with a towel. Slice cleanly, wiping the blade between slices and reheating as necessary. Serve chilled.