Line the bottom and sides of a 9-inch springform pan with wax paper (or grease with non-stick spray). Mix together the Oreo baking crumbs and melted butter and press into the bottom of the pan to form a crust. Refrigerate while making the filling.

Place the softened cream cheese, powdered sugar, vanilla, orange extract, orange zest, and orange juice in a large mixing bowl and beat with an electric handheld mixer, starting on low and increasing to high speed, until smooth.

Heat ½ cup of whipping cream in the microwave in 20-second increments until scalding. Add the semisweet chocolate chips and let sit for 2 minutes. Whisk until smooth and fully incorporated. Add the still-warm mixture to the cheesecake batter and beat on low until combined. Add the remaining ¼ cup of whipping cream and beat on high until fluffy and smooth. Pour over the prepared crust and smooth out the top.

While the cheesecake is chilling, make the ganache topping. Heat the ½ cup of whipping cream in the microwave in 20-second increments until scalding. Add the orange zest to the hot cream followed by the milk chocolate chips and let sit for 2 minutes. Whisk until fully incorporated. Lastly, add the spiced rum (if using) and whisk until combined. Let cool to room temperature before pouring it on top of the slightly chilled cheesecake. Smooth out the top and refrigerate for at least 5-6 hours or until fully set. Serve with whipped cream and garnish with orange slices and chocolate shavings, if desired. Enjoy!