combine powdered sugar and peanut butter blend until the appearance of biscuit mix. spread 3/4 of this mixture on the bottom of the pie shell. combine cornstarch, sugar and salt. add scalded milk and mix well. cook in top of double boiler until mixture thickens add butter and vanilla, then pour into baked pie shell. you can make meringue with the leftover egg whites, but my family prefers whipped topping. sprinkle remaining peanut butter mixture over topping.