Combine the crushed Oreo cookies and melted butter in a medium bowl. Stir together until the mixture looks like wet sand.

Press the Oreo mixture evenly into the bottom and up the sides of a 9-inch pie pan to form a crust. Set it aside.

In a mixing bowl, whisk the instant chocolate pudding mix with 2 ¾ cups of cold milk. Whisk for about 2 minutes or until smooth and thickened.

Pour the pudding mixture into the prepared crust and smooth the top with a spatula.

Spread the thawed whipped topping evenly over the pudding layer.

Sprinkle chocolate shavings on top, if desired, for a decorative finish.

Place the pie in the refrigerator and chill for at least 3 hours, or until fully set and cold.

Slice into pieces, serve, and enjoy!