Recipe(tried): Peanut butter Pie

Peanut Butter Pie

I use Bisquick crust with this filling!
Thanks

1 cup dry milk
1/3 cup sugar
1/2 cup corn starch
5 egg yolks (set aside egg whites)
4 cups water
1 tablespoon butter
2 teaspoons vanilla extract
2 cups powdered sugar
1 cup creamy peanut butter
2 baked pie shells (8 or 9 inch)
whipped topping (optional)

Mix together the first five ingredients. Cook over medium heat stirring constantly until the mixture thickens. Remove form heat; add butter and vanilla. In a small bowl, crumble together the powdered sugar and peanut butter. Spread all but 1/2 cup of the crumb mixture into the bottom of 2 baked pie shells. Pour the hot filling into the shells over the crumb mixture. Bake for 15 minutes in a 350 degree oven. After the pie cools, top with the remaining crumb mixture. Top with whipped topping if desired.