Banana Pudding Pie

Preheat oven to 325°F. Melt unsalted butter in a small saucepan over medium. Cook, whisking constantly, until butter reaches a deep golden brown and smells nutty, about 3 to 5 minutes. Stir together brown butter, finely ground vanilla wafer crumbs, granulated sugar, kosher salt, and ground nutmeg in a bowl.

Lightly grease a 9-inch deep-dish pie plate with butter, and press crust mixture into bottom and up sides of prepared pie plate. Bake until golden brown and firm, 10 to 12 minutes. Remove from oven; let cool on a wire rack while preparing filling.

Whisk together milk, cream, sugar, and salt in a medium saucepan. Cook over medium, whisking often, until steaming, about 5 minutes (do not let milk mixture boil). Remove from heat. Whisk together egg yolks and cornstarch in a medium heatproof bowl until smooth. Using a ladle, slowly drizzle ½ cup steaming milk mixture into egg mixture, whisking constantly until combined. Slowly drizzle egg mixture into remaining warmed milk mixture in saucepan, stirring constantly until combined. Cook milk mixture over medium, whisking constantly, until mixture thickens and begins to simmer (about 200°F), about 5 to 7 minutes. Remove saucepan from heat; whisk in butter and vanilla. Transfer pudding to a medium bowl, and cover with plastic wrap, pressing plastic wrap directly on pudding surface to prevent a skin from forming. Let pudding stand 15 minutes.

Cut 3 of the bananas into ½-inch-thick slices; arrange slices in bottom of cooled crust. Top with pudding; spread into an even layer using a small offset spatula. Cover with plastic wrap, pressing plastic wrap directly on pudding surface to prevent a skin from forming, and chill until set, at least 2 hours or up to 12 hours. 

Just before serving, remove pie from refrigerator. Cut remaining banana into ½-inch-thick slices. Pipe Vanilla Bean Whipped Cream on pie. Arrange banana slices as desired, sprinkle pie with crushed vanilla wafers, and serve.