Chocolate Cookie Crust Banana Cream Pie

Name: Chocolate Cookie Crust Banana Cream Pie
Ingredients: 2 cups coarse chocolate cookie crumbs, plus 1/4 cup for topping; 1/4 cup dark brown sugar; 6 tablespoons unsalted butter, melted; 3 cups whole milk; 4 large egg yolks; 1 teaspoons vanilla extract; 1/2 cup sugar; 1/2 cup cornstarch; 1/4 teaspoon salt; 4 ripe bananas (about 1 1/2 pounds total), peeled, halved lengthwise, and sliced 1/4-inch thick; 1 cup heavy cream, whipped to soft peaks; 2 tablespoons sugar; A few drops vanilla extract