01 - Preheat the oven to 325°F (160°C). Grease a 9-inch springform pan and line the base with parchment paper.
02 - Combine the crushed chocolate sandwich cookies with the melted butter until evenly moistened. Press the mixture firmly and evenly into the bottom of the prepared pan. Bake for 10 minutes, then set aside to cool slightly.
03 - Using an electric mixer, beat the softened cream cheese and granulated sugar on medium speed until completely smooth and free of lumps. Add the creamy peanut butter and sour cream, mixing until fully incorporated.
04 - Add the eggs one at a time, mixing on low speed until each is just incorporated. Stir in the vanilla extract. Avoid overmixing to prevent excess air in the batter.
05 - Pour half of the cheesecake batter over the cooled crust. Drizzle half of the melted dark chocolate over the batter and swirl gently with a knife. Add the remaining batter and repeat with the remaining melted chocolate, creating a marble effect.
06 - Bake for 50 to 55 minutes, until the edges are set but the center still has a slight jiggle. Turn off the oven, crack the door open, and let the cheesecake rest inside for 1 hour to prevent cracking.
07 - Remove the cheesecake from the oven and refrigerate for at least 4 hours, preferably overnight, until fully set.
08 - Heat the heavy cream in a small saucepan until hot but not boiling. Pour over the chopped dark chocolate and let stand for 2 minutes. Stir until smooth and glossy, then blend in the creamy peanut butter.
09 - Spread the peanut butter ganache evenly over the chilled cheesecake. Allow the topping to set for at least 30 minutes before slicing and serving.