Preheat your oven to 350 degrees and prepare a 9” springform pan by spraying with non-stick spray and set aside.
Add Oreo cookies into a food processor and pulse until you have a fine crumb. Add the melted butter and salt and mix until well combined.
Pour the cookie crumbs into the bottom of the springform and use the back of a spoon to gently press the crumbs to form the crust. Be sure to bring the crumbs about 1 inch up the sides.
Bake the crust for 10 minutes and allow to cool.
In the bowl of a stand mixer equipped with a paddle attachment, cream the cream cheese for 2-3 minutes or until smooth and there are no lumps. Scrape the sides and bottom of the bowl occasionally.
Add the sugar and flour and mix until just combined.
Add the hot cocoa packets and mix until just combined.
Pour in the heavy cream and mix on low speed, slowly increasing to high and whip on high for 1-2 minutes.
Add the eggs last, one at a time, mixing until just combined and no more. Scrape the sides of the bowl and give one final mix until smooth.
Pour the batter into the prepared crust and bake for 15 minutes at 350 degrees then, without opening the oven door, reduce the heat to 200 degrees F. and bake for an additional 50-55 minutes or until the center just slightly jiggles. (Should look like Jell-o). Turn off the heat and leave the oven door closed and let the cheesecake rest for 30 minutes.
After 30 minutes, crack the oven door and allow the cheesecake to slowly cool for 15 minutes then remove from the oven and allow to come to room temperature on a wire rack.
Refrigerate for at least 6 hours to overnight
For the topping, add the heavy cream to a microwave save dish and microwave for about 1 minutes or hot. Pour over the chocolate chips and let set for 2-3 minutes then whisk until smooth and thickened.
Allow the ganache to cool for about 5 minutes before pouring over the cheesecake.
Smooth the ganache evenly over the top of the cheesecake and top with whipped cream, mini marshmallows, and chocolate shavings and serve.