Combine crushed Oreos and melted butter in a bowl to form the crust; press mixture into the bottom of a 9x13 inch dish.

In a mixing bowl, beat softened cream cheese and powdered sugar until smooth and creamy.

Fold in thawed Cool Whip until well combined, then spread evenly over the Oreo crust.

In another bowl, whisk together milk and instant pudding mix until combined and thickened.

Add mint extract and a few drops of green gel food coloring to the pudding mixture and stir until desired color is achieved.

Spread the pudding mixture over the cream cheese layer in the dish.

Refrigerate the dessert for at least 4 hours or until fully set before serving.