Triple Chocolate Cheesecake

Place a rack in middle of oven; preheat to 350°. Line bottom of pan with parchment paper. Wrap outside of pan with foil, ensuring foil covers bottom and sides completely (this will help avoid leaks).

Pulse 16 Oreos or other creme-stuffed chocolate sandwich cookies in a food processor until fine crumbs form. (Alternatively, place cookies in a large resealable plastic bag and crush to very fine crumbs using a rolling pin.)

Transfer crumbs to a medium bowl and mix in  2 Tbsp. unsalted butter, melted, slightly cooled, 1 Tbsp. sugar, and ¼ tsp. Diamond Crystal or Morton kosher salt until crumbs are evenly saturated with butter. Transfer to prepared pan and, using a flat-bottomed measuring cup, press crumbs evenly across bottom and about ½” up sides of pan. Bake crust until fragrant, 8–10 minutes.

Set pan inside a large skillet (12”–14”) or other ovenproof dish that can comfortably accommodate it.

Bring a medium pot of water to a simmer.

Place 8 oz. bittersweet chocolate (70% cacao), coarsely chopped, and ½ cup plus 2 Tbsp. heavy cream in a medium heatproof bowl. Place bowl over simmering water and heat, stirring occasionally, until chocolate is melted and smooth, 6–8 minutes (mixture may look slightly curdled; that is okay); remove from heat and set aside.

Pulse three 8-oz. packages cream cheese, 1 cup (200 g) sugar, 1 tsp. Diamond Crystal or ½ tsp. Morton kosher salt, and 1 tsp. vanilla bean paste or vanilla extract in a food processor until mixture is very smooth, about 1 minute. Add melted chocolate mixture and remaining ½ cup plus 2 Tbsp. heavy cream; process until combined, about 45 seconds. Add 4 large eggs and pulse until incorporated, about 45 seconds. (Alternatively, place cream cheese, sugar, salt, and vanilla bean paste or vanilla extract in the bowl of a stand mixer fitted with the paddle attachment. Beat on low speed, scraping down sides and bottom of bowl often, until smooth, 8–10 minutes. Beat in melted chocolate mixture and remaining heavy cream, scraping sides and bottom often, until combined, 5–7 minutes. Lightly whisk eggs in a small bowl; add to stand mixer and mix on low just until incorporated. Using a rubber spatula, fold mixture by hand to ensure chocolate is well combined.)

Pour cream cheese mixture into pan (it’s okay if crust is still warm). Pour simmering water into outer baking dish to come halfway up sides of springform pan; carefully transfer to oven.

Bake cheesecake until edges are set but a 2"–3" circle in the center still wobbles slightly (cheesecake will continue to set after baking), 50–60 minutes. Immediately remove cheesecake from hot water bath (be careful not to get water in it) and let cool until barely warm, 40–45 minutes.

Place 2 oz. bittersweet chocolate (70% cacao), coarsely chopped, in a small heatproof bowl. Heat ¼ cup heavy cream in a small saucepan until simmering; about 2 minutes. Pour over chocolate and let sit for 2 minutes, then stir with a rubber spatula until chocolate is melted and mixture is smooth.

Pour chocolate ganache over cheesecake, using a small offset spatula to spread ganache evenly across surface and up to edges of pan. Chill cheesecake (no need to cover) until firm and fully set, at least 4 hours.

Unmold cheesecake. Using a large offset spatula, transfer to a serving platter. Slice into wedges and serve chilled or at room temperature. Do Ahead: Chocolate cheesecake can be made 1 day ahead. Keep chilled.