Beat softened cream cheese and powdered sugar with an electric mixer until smooth, about 1-2 minutes.
Add peanut butter and mix on medium speed until fully combined, about 1-2 minutes.
Gently fold thawed whipped topping into the peanut butter mixture in 2-3 additions until no white streaks remain.
Pour filling into the chocolate pie shell and smooth the top with a spatula.
Add optional toppings like chocolate sauce or peanuts now or just before serving.
Refrigerate for at least 1 hour before slicing and serving.