For crust: In a medium bowl, stir together crushed cookies and melted butter. Using the bottom of a measuring cup, press mixture into bottom and up sides of a 9-inch pie plate.
Bake until set, approximately 4 minutes. Transfer to a wire rack, and let cool.
For filling: In a small bowl, microwave cream until very hot, approximately 1 minute. Add chocolate morsels, stirring until smooth. Pour chocolate mixture into bottom of prepared crust. Refrigerate until firm, approximately 15 minutes.
In a large bowl, whisk together pudding mix and buttermilk until smooth. Spoon pudding into crust, smoothing top with an offset spatula. Place a piece of plastic wrap directly on surface of filling. Refrigerate until firm, approximately 3 hours.
Spread with whipped topping; garnish with cocoa, if desired.
Recipe by Taste of the South at https://tasteofthesouthmagazine.com/creamy-chocolate-icebox-pie/