Preheat the oven to 350°F. Line a 9x13-inch baking pan with foil, leaving a 2-inch overhang on two sides. Lightly grease.
Combine Oreo crumbs with melted butter. Press firmly into the bottom and slightly up the sides of the pan.
Bake the crust for 10 minutes. Remove and cool. Reduce oven temperature to 325°F.
Melt the bittersweet chocolate gently over a double boiler until smooth. Set aside.
Blend cream cheese until smooth. Add both sugars and cocoa powder and mix until fully incorporated.
Add eggs, egg yolks, and heavy cream. Mix just until combined. Fold in melted chocolate and vanilla.
Pour the filling over the crust and smooth the top.
Bake for 35 minutes, until the center is set but slightly jiggly.
Cool completely, then refrigerate for at least 4 hours.