Mississippi Mud Pie

Ingredients

• 40 Oreo cookies
• 5 Tbsp unsalted butter, melted
• 6 oz bittersweet chopped chocolate
• 1/4 cup unsalted butter
• 1/4 cup water, at room temperature
• 1 Tbsp unsweetened cocoa powder
• 1/4 tsp salt
• 1 Tbsp vanilla extract
• 6 large eggs at room temperature, separated
• 1/2 cup packed light-brown sugar
• 1/2 cup granulated sugar
• 3/4 cup granulated sugar
• 1/2 cup unsweetened cocoa powder
• 1/3 cup cornstarch
• 4 large egg yolks
• 2 1/2 cups whole milk
• 3 Tbsp unsalted butter
• 3 oz bittersweet chopped chocolate
• 2 tsp vanilla extract
• 1 1/4 cups heavy cream
• 3 Tbsp granulated sugar

Directions

1. Make the Oreo crust first. Coat the base and sides of a 9-inch springform pan with butter, place a parchment circle on the base, and butter the parchment lightly as well. Pulse the Oreo cookies in a food processor until they are fine crumbs. Tip the crumbs into a bowl, add 5 Tbsp melted butter, and mix with a fork until the crumbs are evenly damp. Press the mixture across the bottom of the pan and up the sides, stopping about 1/2-inch below the rim. Set the oven to 300 degrees, then place the pan in the freezer for 10 minutes. Move the chilled crust to the oven and bake for 10 minutes. Take it out and let it cool.
2. For the flourless chocolate cake layer, raise the oven to 350 degrees. Put 6 oz bittersweet chocolate chips and 1/4 cup butter in a microwave-safe bowl. Microwave on 50% power in 20 second bursts, stirring each time, until the mixture is melted and smooth; let it cool a little. In a liquid measuring cup, whisk the water with 1 Tbsp cocoa powder, salt, and 1 Tbsp vanilla until smooth, then set it aside. In the bowl of a stand mixer with the whisk attached, beat 6 egg yolks and the brown sugar on medium-high until the mixture turns light and airy and is almost doubled, about 5 minutes. Mix in the melted chocolate just until incorporated, scrape the bowl well, and beat on low for 5 seconds more. Add the water mixture, mix only until blended, scrape again, and beat another 5 seconds.
3. In a clean stand mixer bowl, beat the egg whites until they look foamy. Turn the speed up gradually to high while streaming in 1/2 cup granulated sugar, and continue beating until soft peaks form. If needed, move the yolk and chocolate mixture to another bowl, then wash and dry the mixer bowl thoroughly before using it for the whites.
4. Fold about 1 cup of the whipped whites into the chocolate mixture gently, stopping once combined, about 30 seconds. Add the remaining whites and fold until the batter is almost blended, being careful not to overwork it. Pour the batter into the cooled cookie crust and smooth it out. Bake at 350 degrees for 38 – 42 minutes, until the outer portion looks set and the middle still has a little wobble; it may not look fully baked. Set the pan on a wire rack and cool completely. When cool, cover the pan well with plastic wrap and chill for at least 3 hours or up to overnight.
5. For the chocolate pudding, whisk the granulated sugar, cocoa powder, cornstarch, and salt together in a medium saucepan. Add the egg yolks and stir until combined; the mixture will be thick. Whisk as you slowly pour in the milk. Cook over medium heat, whisking the whole time, until it reaches a boil. Let it bubble for 30 seconds, then take it off the heat and transfer it to a bowl. Stir in the butter, chocolate chips, and vanilla until everything melts together and the pudding is smooth. If you want an extra-sleek texture, you can pass it through a fine strainer. Leave it at room temperature for 15 minutes, then cover it with plastic wrap pressed right onto the pudding’s surface so a skin does not form. Refrigerate for at least 3 hours or overnight.
6. To assemble the pie, take the cake and pudding out of the refrigerator. Stir the pudding until it loosens up, then spread it evenly over the flourless cake layer, keeping it inside the cookie crust edge. Return the pie to the refrigerator for 30 minutes.
7. For the sweetened whipped cream, beat the heavy cream in a mixing bowl with an electric mixer until soft peaks form. Add 3 Tbsp granulated sugar and continue whipping until the peaks are firm. Take the cake from the refrigerator and spread the whipped cream evenly over the top. Release the springform ring, slice the pie, and serve within 3 hours.