Preheat your oven to 325°F (160°C) and grease a 9-inch springform pan. In a mixing bowl, combine the crushed chocolate cookies with melted unsalted butter, mixing until fully incorporated. Press the mixture into the bottom of the pan. Bake for 8-10 minutes until set; then cool completely.

In a mixing bowl, beat the cream cheese until smooth. Gradually add the granulated sugar, mixing well after each addition. Incorporate the eggs one at a time, mixing until smooth. Add vanilla extract, sour cream, and brewed espresso until fully combined. Gently fold in all-purpose flour until just combined.

Wrap the bottom of your springform pan in aluminum foil to prevent leaking. Place it in a roasting pan and fill with water halfway up the sides. Bake for 60-70 minutes until the edges are set and center jiggles slightly. Cool in the oven with the door cracked for 1 hour.

While the cheesecake cools, heat heavy cream in a saucepan until simmering. Pour hot cream over semi-sweet chocolate chips and let sit for a few minutes. Stir until smooth, then mix in brewed espresso. Pour ganache over the cooled cheesecake.

Refrigerate the cheesecake for at least 4-6 hours or overnight. When serving, garnish with chocolate shavings or caramel drizzle. Slice with a warm knife for clean edges.