Once the pie crust is baked lower the oven to 325°.
For the crumb used in bottom of the pie crust and as a topping
1 cup powdered sugar
½ cup peanut butter
Stir until crumbly then divide in half. Spread ½ in the bottom of the baked pie shell. Reserve the other half to sprinkle on top of the meringue topping.
For the pudding
¼ cup cornstarch
⅔ cup sugar
¼ teaspoon salt
3 eggs, separated
2 cups milk
¼ teaspoon vanilla
2 teaspoons butter
Sift the cornstarch, sugar and salt into a sauce pan. In a bowl whisk the egg yolks. Reserve the egg whites for the meringue. Add the milk and vanilla to the yolks and whisk to combine. Pour the egg mixture into the pan with the cornstarch, sugar and salt mixture. Stir until well blended. Cook stirring constantly over medium heat. Add the butter while cooking and cook until the mixture takes on a custard consistency. Strain the pudding to remove any lumps. Pour over the crumb in the pie shell.
For the meringue
3 egg whites
½ teaspoon vanilla
¼ teaspoon cream of tartar
2 tablespoons sugar
Using an electric mixer with a whisk attachment beat the egg whites. Add the vanilla, cream of tartar and sugar and continue beating until glossy and stiff and all the sugar is dissolved. Spread over the pudding.
Sprinkle the remaining crumb mixture on top of the meringue.
Bake at 325° for 25 minutes or until brown.
Cool completely and refrigerate. Serve cold.