Preheat the oven to 325°F (160°C).

In a mixing bowl, combine crushed chocolate cookies and melted butter. Press the mixture into the bottom of a springform pan to form the crust.

In a large mixing bowl, beat the softened cream cheese until smooth.

Add granulated sugar and mix until combined.

Add eggs one at a time, mixing well after each addition.

Stir in vanilla extract, sour cream, brewed espresso, and flour until smooth.

Fold in chocolate chips.

Pour the cheesecake filling over the crust in the pan and smooth the top.

Bake for about 60 minutes, or until the edges are set but the center is slightly jiggly.

Let it cool at room temperature, then refrigerate until chilled.

In a saucepan, heat the heavy cream until just about to simmer.

Remove from heat and add the chopped chocolate. Stir until melted and smooth.

Add brewed espresso and mix well.

Pour the ganache over the cooled cheesecake and spread evenly.

Chill the cheesecake in the refrigerator until the ganache is set.

Slice and serve, optionally garnished with whipped cream and chocolate shavings.