Reserve 9 cookies for to go around the edge. (You can crush all the cookie for the crust if you want. Below is what I did.) Take the remaining cookies, place them in a zip-top bag, and pound them with a meat mallet or a rolling pin until finely crushed.
In a medium-sized bowl, mix the crushed cookies and melted butter together. Mix with a fork until the cookies are all coated with butter. Using the bottom of a flat glass, press the mixture into the bottom of a pie plate in an even layer. Take the reserved cookies and place them around the edge of the pie plate. Refrigerate until the filling is ready.
Pie filling
In the bowl of your electric mixer, beat the cream cheese and cookie butter until smooth. Stop the mixer and add the marshmallow fluff. Mix until combined and smooth.
Fold in the Cool Whip by hand. Pour the mixture into your prepared pie crust. Chill for at least 4 hours to overnight. Serve cold. Refrigerate any leftovers. The pie will keep in the fridge 3 to 4 days before the crust begins to get soggy.