Crush 16 cookies with a food processor or by hand; Add the butter and combined well with the cookies. Press firmly into an ungreased 9-in. square dish. Set aside for later.
In a large bowl, beat the cream cheese, peanut butter and 1 cup confectioners' sugar until smooth. Fold in half of the whipped topping. Spread over crust.
Cut each peanut butter cups into 6 pieces. Sprinkle peanut butter layer with 6 of the chopped peanut butter cups. Reserve the remaining peanut butter cups for the top.
In another large bowl, beat the milk, pudding mix and remaining confectioners' sugar on low speed for 2 minutes Let stand for 2 minutes until pudding starts to set. Fold in remaining whipped topping.
Spread the chocolate pudding mixture over the peanut butter cups. Chop the remaining cookies and peanut butter cups and sprinkle over the top. Cover and chill for at least 3 hours.