Crush oreo cookies. You can use a food processor or crush them in a resealable plastic bag. You should get a little over 3 cups.
Cream together softened cream cheese and powdered sugar until smooth.
Whisk together chocolate pudding and milk. Allow to set for 2 minutes.
Fold chocolate pudding into cream cheese mixture. Fold in whipped topping.
In a 9x13 inch dish, place about 1 1/2 cups of Oreos in the bottom of the dish. Spread 1/2 of the pudding mixture on top. Top with another 1 - 1 1/2 cups of crushed Oreos. Top with remaining pudding mixture and more Oreo crumbs. Decorate as desired. Cover and chill for at least 1 hour before serving.
Notes
30 Oreos should get you about 3 cups of crushed Oreos. You can use more or less if you like. They don't need to be fine crumbs, you still want some bigger pieces. I used black writing gel to write the RIP on the Milano cookies. Nutrition information for estimation purposes only.