In a large bowl, mix together the peanut butter and sweetened condensed milk. Gently fold in the Cool Whip. When Cool Whip is thoroughly combined into the peanut butter sweetened condensed milk mixture, stir in half the Reese's Pieces and the chocolate chips.
Pour the mixture into your premade pie crust. Top with the remaining Reese's Pieces.
For best texture, set in the fridge for an hour prior to diving in.
Notes
*Use any kind of pie crust you like. I prefer a chocolate crust and to keep in gluten free, do a gluten free chocolate pie crust.