Prepare the Crust:

1. In a medium bowl, combine the graham cracker crumbs and melted butter. Mix until the texture resembles wet sand.
2. Press the mixture into the bottom of a greased 9-inch springform pan, smoothing it out evenly.
3. Pour the melted dark chocolate over the crust, spreading evenly. Refrigerate for 10 minutes to set.

2. Make the Cheesecake Filling:

1. In a large mixing bowl, beat the softened cream cheese and granulated sugar until smooth.
2. Add the eggs one at a time, mixing thoroughly after each addition.
3. Stir in vanilla extract, sour cream, and heavy cream until the batter is creamy and thick.

3. Assemble the Layers:

1. Pour the cheesecake filling over the prepared crust, smoothing the top with a spatula.
2. Refrigerate the cheesecake for at least 4 hours or overnight to set.

4. Prepare the Ganache Topping:

1. Heat the heavy cream in a small saucepan until it begins to simmer (do not boil).
2. Pour the hot cream over the dark chocolate chips in a bowl. Let it sit for 2-3 minutes, then stir until smooth.

5. Add Ganache and Finish:

1. Pour the ganache over the chilled cheesecake, spreading evenly with a spatula.
2. Refrigerate for at least 1 hour to set the ganache.
3. Slice, serve, and enjoy!