01 - Preheat the oven to 325°F. Grease a 9-inch springform pan and line the base with parchment paper.
02 - Combine the crushed chocolate sandwich cookies with melted butter until evenly moistened. Press the mixture firmly into the bottom of the prepared pan to create an even layer. Bake for 10 minutes, then set aside to cool slightly.
03 - Using an electric mixer, beat the softened cream cheese and granulated sugar together until completely smooth and free of lumps. Add the peanut butter and sour cream, blending until fully incorporated.
04 - Add the eggs one at a time, mixing on low speed until each is just barely 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 surface and gently swirl with a butter knife. Pour in 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 but the center still has a slight jiggle when gently shaken. Turn off the oven, crack the door open, and allow the cheesecake to rest inside for 1 hour as it slowly cools.
07 - Transfer the cheesecake to the refrigerator and chill for at least 4 hours, preferably overnight, until fully set and firm.
08 - Heat the heavy cream in a small saucepan until hot but not boiling. Pour the hot cream over the chopped dark chocolate and let stand for 2 minutes. Stir until silky smooth, then blend in the peanut butter until fully combined.
09 - Spread the ganache evenly over the surface of the chilled cheesecake. Allow the topping to set for at least 30 minutes before slicing into 12 portions and serving.