01 - Preheat oven to 325°F. Grease a 9-inch springform pan and line the base with parchment paper.
02 - Combine crushed chocolate sandwich cookies with melted butter until evenly moistened. Press the mixture firmly into the bottom of the prepared pan to form an even crust. Bake for 10 minutes, then set aside to cool slightly.
03 - Using an electric mixer, beat softened cream cheese and granulated sugar on medium speed until completely smooth and free of lumps. Add creamy peanut butter and sour cream, blending until fully incorporated.
04 - Add eggs one at a time, mixing on low speed until each is just incorporated. Stir in vanilla extract. Avoid overmixing to prevent air bubbles.
05 - Pour half of the filling over the cooled crust. Drizzle half of the melted dark chocolate over the batter and gently swirl with a butter knife. Add the remaining batter and repeat with the remaining melted chocolate, creating decorative swirls throughout.
06 - Bake for 50 to 55 minutes, until the edges are set and the center still has a slight jiggle. Turn off the oven, crack the door open, and allow the cheesecake to cool gradually inside for 1 hour.
07 - Remove the cheesecake from the oven and transfer to the refrigerator. Chill for a minimum of 4 hours, or ideally overnight, until completely firm.
08 - Heat heavy cream in a small saucepan until hot but not boiling. Pour the hot cream over the finely chopped dark chocolate and let stand for 2 minutes. Stir until smooth and glossy, then blend in the creamy peanut butter until fully combined.
09 - Spread the ganache evenly over the chilled cheesecake. Allow the topping to set for at least 30 minutes before slicing and serving.