Step 1

Make the crust: Preheat the oven to 350°F (180°C). Grease a 9-inch (23 cm) springform pan with nonstick spray and line the sides with a strip of parchment paper, trimming it flush with the top of the pan.

Step 2

In a large bowl, stir together the cookie crumbs and melted butter until the crumbs are evenly moistened. Transfer the crumbs to the prepared pan and use the bottom of a measuring cup to press them into an even layer over the bottom of the pan. Set the pan aside while you make the brownie layer.

Step 3

Make the brownie layer: In a large glass bowl, combine the chocolate and butter and microwave on high power, 30 seconds or until melted and smooth.

Step 4

In a separate large bowl, whisk together the granulated sugar, brown sugar, salt, vanilla, and eggs until lightened in color and foamy, about 1 minute. Pour in the melted chocolate mixture and whisk until smooth. Add the flour and stir until just combined.

Step 5

Pour the batter over the crust in the pan and smooth out the top with a rubber spatula. Bake until a toothpick inserted halfway between the center and the edge comes out clean, about 40 minutes.

Step 6

Meanwhile, make the pudding layer: In a medium saucepan, whisk together the granulated sugar, cocoa powder, flour, and salt until combined. Add the egg yolks and a splash of the milk and stir until it the mixture forms a thick, smooth paste. Add the remaining milk and whisk until smooth. Set the pan over medium heat and cook, stirring continuously, until the mixture starts to bubble and thicken, 8-10 minutes. Remove the pan from the heat, and add the butter and vanilla and stir until the butter has melted and the mixture is smooth and well combined.

Step 7

When the brownie layer is ready, transfer the pan to a wire rack, pour the warm pudding over the brownie layer, and smooth out the top with a rubber spatula. Let cool to room temperature, about 1 hour. Cover and refrigerate for at least 4 hours, or up to 1 day.

Step 8

When ready to serve, whisk the chilled cream in a medium bowl until it forms stiff peaks.

Step 9

Remove the pie from the refrigerator. Remove the outer ring of the springform pan, then peel away and discard the strip of parchment paper and set the pie on a serving plate. Spread the whipped cream over the top of the pie, and dust with additional cocoa powder. Serve the pie chilled.

Step 10

Enjoy!