In a mixing bowl, beat together peanut butter, powdered sugar, and softened cream cheese until smooth.
Fold in half the Cool Whip (about 4 oz) until fully combined. Spread this peanut butter layer evenly into the pie crust.
In a separate bowl, whisk together instant chocolate pudding mix and cold milk for about 2 minutes until thickened.
Spread pudding evenly over the peanut butter layer.
Spread remaining Cool Whip over the pudding layer to create a smooth finish.
Refrigerate at least 2 hours, or overnight for best results.
Before serving, sprinkle with chocolate or peanut butter chips and drizzle with melted peanut butter or chocolate if desired. Slice and serve chilled.