Crunch up 2 out of the 3 rows of the Oreos & spread them out in the bottom of a 9x13 dish.
Pour the melted butter over the top of the cookies.
In a large mixer bowl, beat the cream cheese until light and fluffy.
Slowly add in the milk, sugar, and dry pudding mix & mix until combined.
Slowly fold in the whipped topping.
Pour the mixture over the crushed cookies in the pan.
Crunch up the remaining cookies & sprinkle them over the top.
Add a generous amount of rainbow sprinkles.
Carefully transfer to the freezer and freeze for several hours to set before serving. The mixture will be thin and will splash if you move too quickly - so just be cautious when moving it to the freezer to firm up.