Peanut butter banana pie

Crust:
1 cup reduced-calorie vanilla wafer crumbs (about 30 cookies)
2 tablespoons butter or stick margarine, melted and cooled
1 large egg white, lightly beaten
Cooking spray

Filling:
2/3 cup sugar
3 1/2 tablespoons cornstarch
1/4 teaspoon salt
1 1/3 cups 1% low-fat milk
2 large eggs, lightly beaten
2 tablespoons creamy peanut butter
1 teaspoon vanilla extract
2 1/2 cups sliced banana
1 1/2 cups frozen whipped topping, thawed

Preparation
Preheat oven to 350°.
To prepare crust, combine first 3 ingredients in a bowl, tossing with a fork until moist. Press into bottom and up sides of a 9-inch pie plate coated with cooking spray. Bake at 350° for 12 minutes; cool crust on a wire rack.
To prepare the filling, combine the sugar, cornstarch, and salt in a small heavy saucepan. Gradually add the milk, stirring with a whisk until well-blended. Cook over medium heat until mixture comes to a boil; cook for 1 minute, stirring with a whisk. Gradually add about 1/3 cup hot custard to beaten eggs, stirring constantly with a whisk. Return egg mixture to pan. Cook over medium heat until thick (for about 1 minute); stir constantly. Remove from heat, and stir in peanut butter and vanilla. Cool slightly.
Arrange banana slices in bottom of prepared crust; spoon filling over bananas. Press plastic wrap onto the surface of filling; chill 4 hours. Remove plastic wrap. Spread whipped topping evenly over filling. Chill.