Begin by finely crushing 20 peanut butter sandwich cookies in a blender or food processor until they resemble fine crumbs. In a microwave-safe bowl, melt ½ cup of butter and then combine it with the crushed cookies. Press this mixture firmly into the bottom of an 8x8-inch baking dish, creating an even layer. Place the dish in the freezer for at least 30 minutes for the crust to firm up.

While the crust firms up, prepare the chocolate layer by mixing 1 package of instant chocolate pudding with 1½ cups of milk in a medium bowl. Whisk the mixture vigorously until fully combined and smooth. Once the pudding begins to thicken, cover it with plastic wrap and place it in the refrigerator to chill for about 10 minutes.

In the meantime, take 8 ounces of softened cream cheese and beat it in a mixing bowl until smooth. Add in 1 cup of confectioners' sugar, ½ cup of creamy peanut butter, and 1 teaspoon of pure vanilla extract. Mix these ingredients until well combined. Finally, gently fold in 1 cup of Cool Whip to lighten the mixture.

Once the crust is set, spread the creamy cheese mixture evenly over the chilled cookie crust. Then, retrieve the chocolate pudding from the fridge and pour it over the cream cheese layer, smoothing it out gently until even. Top this layer with the remaining Cool Whip, spreading it to cover the chocolate layer completely.

To ensure the layers hold together, place the prepared Chocolate Peanut Butter Dream Bars in the freezer for another 30 minutes. Before serving, sprinkle crushed cookies and optional milk chocolate or peanut butter chips on top for an added crunch. Slice into squares with a warm knife for clean edges.