1 package Oreo cookies (36 cookies)
6 tablespoons butter melted
1 (8 ounce) package cream cheese softened
1/4 cup granulated sugar
3 1/4 cups milk plus 2 tablespoons, divided
1 (16 ounce) tub whipped topping thawed and divided
2 (3.9 ounce) packages instant chocolate pudding mix (see note 1)
1/4 cup mini chocolate chips for garnish
In a food processor, or in a plastic bag with a rolling pin, crush the Oreo cookies into crumbs. In a medium bowl, add Oreo crumbs and melted butter and stir to combine.
Pour into a 9-inch by 13-inch baking dish. Using the bottom of a measuring cup, press the crust firmly and evenly into the bottom of baking dish.
In a standing mixer fitted with the paddle attachment, or with an electric mixer, add cream cheese and beat until fluffy. Add sugar and 2 tablespoons of milk and beat until combined.
Stir in half of the whipped topping (about 8 ounces) to cream cheese mixture. Spread cream cheese mixture over cookie crust and refrigerate to set, about 10 minutes.
While the cream cheese layer is chilling, using a standing mixer fit with the paddle attachment, or with an electric mixer, on medium speed add instant pudding and remaining 3 ¼ cups milk. Beat until mixture begins to thicken, about 5 minutes.
Spread pudding mixture over chilled cream cheese layer and refrigerate to set, about 10 minutes.
Once set, gently spread remaining 8 ounces whipped topping over pudding layer and garnish with mini chocolate chips. Cover loosely with cling wrap and chill for 4 hours, or freeze for 1 hour. Cut into slices and serve.