Mississippi Mud Pie

For the Crust - Adjust oven rack to middle position and preheat oven to 350ºF (175ºC). In a food processor, process cookie pieces and salt until fine crumbs form, about 30 seconds. Add melted butter to cookie mixture and pulse until crumbs begin to clump together, about 4 pulses. Transfer mixture to 9-inch pie plate. Using your fingers, press mixture into bottom and up the sides of the pie plate, then compress firmly using a flat-bottomed drinking glass or measuring cup. Keep pressing until the crumbs form a compact, even layer across the bottom of the baking dish. Wash and dry food processor bowl; set aside.

For the Crust - Bake until just set, 10 to 12 minutes. Crust may puff slightly while baking; if necessary, gently press down with a flat-bottomed drinking glass or measuring cup immediately after baking. Let cool slightly on a wire rack, about 10 minutes.

For the Brownie Layer - Fill a small saucepan with 1 inch water and bring to a simmer over medium heat. In a heat-proof bowl large enough to nest in the saucepan without touching the water, combine chocolate, butter, and oil. Set bowl over the saucepan and cook, stirring occasionally, until melted and smooth, about 2 minutes. (Alternatively, place chocolate, butter, and oil in a large microwave-safe bowl. Microwave chocolate mixture on medium power in 30-second intervals, stirring thoroughly between intervals, until melted and smooth, 2 minutes total.) Remove from heat and let stand until slightly cooled, about 10 minutes.

For the Brownie Layer - In a second large bowl, beat eggs, sugar, vanilla, and salt with a hand mixer on medium-high speed until pale yellow and tripled in volume, about 5 minutes. (Alternatively, in the bowl of a stand mixer fitted with the whisk attachment, beat eggs, sugar, vanilla, and salt on medium-high speed until pale yellow and tripled in volume, 3 to 5 minutes.) Using a flexible spatula, fold 1/3 egg mixture into slightly cooled chocolate mixture. Gently fold in remaining egg mixture in 2 batches until no streaks remain.

For the Brownie Layer - Using a fine-mesh sieve, sift flour and cocoa powder into chocolate mixture. Using a flexible spatula, fold dry ingredients into chocolate until just combined. Scrape batter into cooled crust, using a flexible or offset spatula to spread it into an even layer. Bake until a toothpick inserted in the center comes out with several moist crumbs attached, about 18 minutes. Let cool on a wire rack for 1 hour, then refrigerate until completely cool, about 1 hour.

For the Chocolate Pudding - In the now-clean food processor bowl, process chocolate, brown sugar, espresso granules (if using), and salt until finely ground, about 20 seconds. Add yolks and vanilla extract; pulse until thoroughly combined and chocolate mixture begins to clump together, about 5 pulses.

For the Chocolate Pudding - In a small saucepan, bring cream to a boil over medium heat, stirring constantly. With food processor running, slowly and carefully pour hot heavy cream through chute until chocolate mixture is melted and smooth, about 35 seconds, stopping to scrape down sides as needed. Pour pudding over brownie layer and gently press plastic wrap against surface of pudding. Refrigerate until completely chilled and set, at least 2 hours or up to 2 days.

For the Whipped Cream - In a large bowl, whip cream, sugar, and vanilla together using a hand mixer on medium speed until mixture holds medium-stiff peaks, 1 to 2 minutes. (Alternatively, in the bowl of a stand mixer fitted with the whisk attachment, whip cream, sugar, and vanilla together on medium speed until mixture holds medium-stiff peaks, about 1 to 3 minutes.) Using a flexible or offset spatula, spread whipped cream over chocolate pudding layer and garnish with chopped pecans.