In a food processor or blender, blend Oreos (whole cookies) into fine crumbs. Add melted butter and mix until combined. Press the mixture into the bottom of a 9x13-inch dish and place in the freezer or the refrigerator for 5 minutes.
Layer 1
In a medium-sized bowl, whip the cream cheese until fluffy with an electric mixer. Add in the sugar and milk. Mix until combined. Stir in 1 cup Cool Whip, then spread the mixture lightly over the crust. Place in the freezer or fridge for another 5 to 10 minutes.
Layer 2
In a separate bowl, whisk the pudding and cold milk together until thick. Once thickened, spread over the top of the cream cheese layer. Place back in the fridge for another 5 to 10 minutes to allow the pudding to set.
Topping
Once the pudding has set, spread the remaining Cool Whip on top and sprinkle with chocolate chips or crushed Oreos. Store in the refrigerator for 2 to 3 hours. Slice just before serving and enjoy while cold.
Notes
Oreo's: Keep the cream in the center. You want to crush the whole cookie pretty fine, so I find using a blender or food processor is easiest. Pudding: Make sure it's the instant chocolate pudding. Do not use the cook and serve variation.Cool whip: If you prefer a homemade cool whip, it is fairly easy to make. Make ahead: This dessert can easily be made 24 hours in advance. The crust will get softer the longer the pudding sits, so I don't like to prep it more than 48 hours in advance. You can also make the crust and then keep the layers in separate bowls until ready to assemble.