Spray a 9-inch pie pan with cooking spray and set aside.
Using a food processor, crush the oreo cookies until fine. Add the butter and pulse a few times to combine.
Pour the crumb mixture into the bottom of the pie pan and press along the bottom and sides. Place into the fridge to cool and harden.
In a medium saucepan, melt the marshmallow fluff over medium-low heat, stirring constantly until completely melted.
Remove from heat and pour into a large bowl. Stir in mint extract and food coloring. Allow to cool.
Once the fluff mixture has cooled, stir in the whipped topping until combined and add more food coloring if needed to reach desired color tone.
Pour the mixture into prepared crust and top with mini chocolate chips. Refrigerate until firm for at least 4 hours or overnight (don't skip this step!) Serve and enjoy!
Note: You can even freeze this dessert to make it more like an ice cream pie.