For the filling, beat the cream cheese, peanut butter, sugar, butter, and vanilla in a large bowl until smooth and creamy. Fold in whipped cream until well combined. Gently spoon into the crust. Garnish with pieces of mini reeses peanut butter cups. Place the chocolate chips in a glass bowl into the microwave and cook for 30 seconds then remove & stir; return to the microwave and cook for 20 seconds then remove and stir; return to the microwave (if needed) for 10 seconds then remove and stir, until creamy and melted. Place the melted chocolate chips into a small ziplock bag then cut a tiny edge off one of the corners. Pipe the melted chocolate over the top of the pie. Place into the refrigerator for a couple of hours to set. Serve & enjoy!