MAKE-AHEAD MISSISSIPPI MUD PIE

Steps:

• Preheat oven to 375 degrees. In a food processor, grind wafers and pecans until fine crumbs form. Add melted butter; process until moistened. Transfer mixture to a 9-inch pie plate; press into bottom and up sides (use the base of a dry measuring cup to help). Bake until fragrant, 8 to 10 minutes; let cool.
• Place a large fine-mesh sieve over a medium bowl; set aside. In a medium saucepan, off heat, whisk together 2/3 cup sugar, cocoa powder, cornstarch, and salt. A few tablespoons at a time, whisk in milk, being sure to incorporate the cornstarch. Whisk in egg yolks.
• Over medium heat, whisking constantly, cook mixture until the first large sputtering bubble forms. Reduce heat to low; continuing to whisk constantly, cook 1 minute. Remove from heat; immediately pour through sieve into bowl. Stir in teaspoon vanilla and 2 tablespoons cold butter.
• Pour pudding into crust. Place plastic wrap directly on surface (to prevent skin from forming); chill at least 2 hours and up to 1 day. Just before serving, beat cream, remaining teaspoon sugar, and remaining teaspoon vanilla until soft peaks form. Spread whipped cream over pudding, and sprinkle with pecans.