In a 9x13 casserole dish, place a layer of cookies.
In a large mixing bowl, beat together the cream cheese and powdered sugar until completely blended. Stir in ½ cup coarsely chopped oreos. Fold in 1 ½ cups whipped topping.
Spoon the cream cheese mixture in dollops over the cookies and press into an even layer.
In another mixing bowl, beat together the pudding mix and milk for 5 minutes or until the pudding has thickened. (Check the package instructions.)
Spread the pudding over the cream cheese layer. Top with a layer of the remaining whipped topping.
Place the remaining cookies in a zip top bag and crush. Sprinkle over the whipped topping layer.
Cover and return the dish to the refrigerator to store overnight to allow the cookies to soften. Drizzle chocolate over the crushed cookies before serving.