In a blender or food processor, pulse the Oreos (both cookies and cream filling) until fully crushed into fine crumbs. The consistency should resemble coarse sand with no large pieces remaining.
In a large bowl, combine the Oreo crumbs with the melted butter, mixing until every crumb is evenly coated. The mixture should clump slightly when pressed, indicating that the butter is well absorbed.
Press the mixture evenly into a 9- or 10-inch pie pan, using the bottom of a measuring cup to pack it firmly across the bottom and slightly up the sides. This helps the crust hold its shape once chilled.
Place the crust in the refrigerator to chill while preparing the filling. The cooling step helps the crust set and keeps it stable when the thick filling is added.
2. Filling
In a stand mixer or large mixing bowl, combine the pudding mix and 3 cups heavy cream. Beat with an electric mixer until the mixture becomes very thick and fully blended. Do not prepare the pudding according to the package directions—mixing directly with heavy cream produces a dense, mousse-like texture essential for this pie.
Add the cool whip, mint extract, and desired amount of green food coloring. Mix on low speed just until everything is incorporated. The filling should be smooth, fluffy, and evenly tinted green.
Spread the filling evenly over the chilled crust, smoothing the top. Cover the pie pan tightly with plastic wrap and refrigerate for 4–8 hours. The extended chilling helps the filling firm enough to slice cleanly.
