Start by lightly greasing a 9x13 inch pan with nonstick spray.

In a blender, crush Oreo cookies until they turn into fine crumbs. Melt unsalted butter and mix it with the crushed cookies until fully combined. Press into the bottom of the prepared pan.

In a medium bowl, combine creamy peanut butter, powdered sugar, and room temperature cream cheese. Blend until smooth and creamy. Fold in half of the Cool Whip until well incorporated, then spread over the Oreo crust.

In another bowl, whisk together the instant chocolate pudding dry mix and milk for about 2 minutes. Pour the chocolate pudding over the peanut butter mixture and smooth it out.

Spread the remaining Cool Whip over the chocolate layer.

Finely crush the Butterfinger candy bars and sprinkle over the whipped cream layer.

Cover the dessert and refrigerate for at least 1 hour to allow the layers to set.