Preheat the oven to 350 degrees F. Prepare a 9-inch springform pan by covering the bottom and sides with aluminum foil.
Place Oreos in a food processor and pulse until no large chunks remain. Add in sugar and melted butter and pulse to combine until no dry crumbs remain. Press the mixture evenly into the prepared pan and bake until set, about 15 minutes. Let cool completely on a wire rack. Reduce oven temperature to 250 degrees.
24 Oreos, 2 tbls sugar, 3 tbls melted butter
Combine 8 oz chocolate and 1/2 cup plus 2 tablespoons of heavy cream in a medium glass bowl and microwave at 50 percent power for 2 minutes. Whisk until smooth. Set aside and let cool.
8 oz milk chocolate, ½ cup heavy cream, 2 tblsp heavy cream
In a separate bowl, whisk cocoa powder, sugar and salt until no lumps remain.
3 tbls cocoa powder, ½ cup sugar, ¼ teaspoon salt, 2 tbls sugar
Using a stand mixer fitted with the whisk attachment, beat the cream cheese until smooth and no lumps are visible. Scrape down the sides of the bowl as needed.
4 - 8 oz packages cream cheese
Add in cocoa mixture and beat until combined. Add in melted chocolate mixture and vanilla extract and beat until combined. Add the eggs 1 at a time and mix until incorporated. Scrape the sides of the bowl after each addition.
1 tbls vanilla extract, 5 eggs
Pour batter into springform pan and cover pan tightly with aluminum foil. Place on rimmed baking sheet and bake for 1 hour. Remove foil and bake until the edges are set and the middle has a slight wobble, about 45 more minutes. Remove from the oven and let cool completely on a wire rack. Cover with plastic wrap and refrigerate overnight.