Step 1: Prepare the Crust. Crush 24 chocolate sandwich cookies into fine crumbs using a food processor or by placing them in a sealed bag and crushing with a rolling pin.
Step 2: Combine the crumbs with 5 tablespoons of melted butter until evenly moistened.
Step 3: Press the mixture firmly into the bottom of a 9x13-inch dish. Chill in the refrigerator for at least 15 minutes to set.
Step 4: Make the Cream Cheese Layer. In a medium bowl, beat 8 ounces of softened cream cheese with ½ cup of powdered sugar until the mixture is smooth and free of lumps.
Step 5: Gently fold in 8 ounces of thawed whipped topping until it is fully incorporated, being careful to maintain its airy texture.
Step 6: Spread this cream cheese mixture evenly over the chilled cookie crust using an offset spatula.
Step 7: Prepare the Pudding Layer. In a separate bowl, whisk together one 3.4-ounce package of vanilla instant pudding mix and one 3.4-ounce package of chocolate instant pudding mix with 2¾ cups of cold milk for two minutes, or until well combined.
Step 8: Allow the pudding mixture to rest for a few minutes until it begins to thicken slightly.
Step 9: Carefully pour the thickened pudding over the cream cheese layer, spreading it gently to create an even surface.
Step 10: Final Assembly. Spread the remaining 8 ounces of whipped topping evenly over the pudding layer.
Step 11: Sprinkle 1 cup of crushed Butterfinger candy bars generously and evenly over the top layer of whipped topping.
Step 12: Cover the dish and refrigerate for at least four hours, or preferably overnight, to allow the layers to set completely for easier slicing and optimal flavor.