To Prepare the Crust:
Preheat your oven to 325°F (163°C). Prepare a 9-inch springform pan by wrapping the bottom and sides with three layers of heavy-duty aluminum foil to create a waterproof seal. Spray the pan with nonstick cooking spray.
In a food processor, pulse the Oreo cookies until you have fine crumbs. You should have about 1 cup of crumbs. Add the melted butter and pulse until the mixture is moistened.
Press the cookie crumb mixture into the bottom and halfway up the sides of the prepared pan. Bake for 10 minutes, or until the crust is fragrant. Set aside to cool slightly while you prepare the filling. Maintain oven temperature.
To Make the Filling:
In a microwave-safe bowl, melt the chopped chocolate in 30-second intervals, stirring between each, until smooth. Set aside to cool slightly.
In a large mixing bowl, beat the cream cheese on medium speed using an electric mixer until smooth and free of lumps. Scrape down the bowl as needed.
Add the granulated sugar, heavy cream, and cocoa powder to the cream cheese. Beat until well combined, ensuring that all the cream cheese is incorporated.
Add the eggs and yolk one at a time, beating on low speed until just combined after each addition.
Gradually mix in the peppermint extract and the melted chocolate until the filling is smooth. Be careful not to overmix.
Pour the cheesecake batter into the cooled crust. Tap the pan gently on the counter to release any air bubbles.
Place the springform pan in a larger roasting pan. Carefully pour boiling water into the roasting pan until it comes about halfway up the sides of the cheesecake pan.
Bake at 325°F (163°C) for 1 hour to 1 hour 15 minutes, or until the top is slightly dry but the center remains wobbly like Jell-O. Avoid overbaking.
Turn off the oven and crack the oven door open slightly. Allow the cheesecake to cool in the oven for 45 minutes to prevent cracking.
Remove the cheesecake from the oven and transfer it to a wire rack to cool to room temperature. Then, refrigerate for at least 4 hours or until completely chilled.
To Make the Topping:
Place the chocolate chips in a medium heatproof bowl.
In a small saucepan, heat the cream until it just begins to simmer. Pour the hot cream over the chocolate chips and let it sit for 3 minutes.
Stir the mixture until the chocolate is completely melted and smooth. If needed, let the mixture cool slightly to thicken.
Pour the ganache over the chilled cheesecake, spreading it evenly over the top.
Garnish with crushed candy canes for a festive touch.
Serving: Serve the cheesecake immediately or store it in the refrigerator for up to 5 days.
Storage: Store leftovers covered in the refrigerator for up to 5 days.