Preheat your oven to 350°F (175°C). Press the softened chocolate chip cookie dough evenly into the bottom of a greased 9x13-inch baking pan. Bake for 10-12 minutes or until the edges are lightly golden. Allow the crust to cool completely while you prepare the next layers.
In a medium bowl, whisk together the instant chocolate pudding mix and cow's milk. Whisk until smooth and set aside for about 5 minutes to thicken.
In another bowl, use an electric mixer to beat the softened cream cheese until smooth. Add the marshmallow creme or fluff, mixing until well combined. Fold in the Cool Whip gently until light and fluffy.
Once the cookie crust has cooled, spread the chocolate pudding layer evenly over the crust. Spoon the cream cheese and marshmallow layer on top, smoothing it out with a spatula. Sprinkle half of the chopped Oreo cookies over the cream cheese layer.
Drizzle the warmed hot fudge over the top, and sprinkle the remaining chopped Oreo cookies. Cover the baking pan with plastic wrap and refrigerate for at least 4 hours, or overnight, to allow the bars to set properly.
Once set, remove the bars from the refrigerator and lift them out of the pan using the parchment paper. Cut into squares and serve chilled.