Mix the Oreo crumbs and melted butter together in a small bowl, then press the crumbs into the bottom of a 13x9 dish or pan. Set the crust in the freezer for about 20 minutes.

While the crust is in the freezer, use an electric hand mixer to blend together the cream cheese and powdered sugar in a large bowl until smooth.

Add 8 ounces of whipped topping and continue mixing at low speed until well mixed.

In a separate large bowl, add the chocolate pudding mix and cold milk and whisk for about 2 minutes or until the chocolate pudding starts to get thick. Then, let the pudding rest for another 2-3 minutes to thicken more.

Remove the crust from the freezer, and spread the cream cheese mixture evenly over the cookie crumb crust. Then sprinkle 1/2 cup of chopped pecans and gently press them into the cream cheese layer.

Spread the chocolate pudding over the cream cheese and pecan layers, and finally, spread the remaining 8 ounces of whipped topping over the chocolate pudding. Cover the dessert with plastic wrap, and chill in the refrigerator for at least 4 hours. Overnight chilling is best.

Right before serving, drizzle the caramel sauce and chocolate syrup over the top of the dessert, and sprinkle the remaining 1/2 cup of chopped pecans. Slice and serve chilled.