In a medium bowl, combine the crushed chocolate cookies and melted butter. Press the mixture evenly into the bottom of a 9x13 inch baking dish.
In a separate bowl, beat together the softened cream cheese, powdered sugar, and peppermint extract until smooth. Gently fold in 1 cup of whipped topping.
Spread the cream cheese mixture evenly over the cookie crust.
In another bowl, whisk together the instant chocolate pudding mix and milk until well combined and slightly thickened. Let stand for 5 minutes.
Spread the chocolate pudding mixture over the cream cheese layer.
Top with the remaining 1 cup of whipped topping. Sprinkle with chocolate shavings and crushed peppermint candies.
Refrigerate for at least 2 hours before serving.
Notes
This dessert is best served chilled. It can be made a day in advance.