Tastes best when made as a double layer cake. Even better when the finished cake refrigerates over night and is served cold. Unfortunately this can't be rushed. DO NOT put Cool Whip on until cake is cool, or the cool whip turns into a funky mess.
1 German chocolate cake mix (and eggs, water, oil to make it)
Caramel topping (Smuckers squeezable caramel topping works best)
Bake the cake according to directions. When the cakes finish, let them cool on a wire rack. Place the first layer on your cake plate, then with the rod end of a plastic stirring spoon, poke several holes in the bottom layer of the cake. Open the condensed milk and slowly pour the milk over the cake, letting some seep into the holes. Then do the same with the caramel. Sprinkle a light layer of Butterfinger crumbles over top. Cover the bottom layer in a layer of Cool Whip. Gently place the second layer on top and repeat the previous steps to the second layer. Finish covering the sides with Cool Whip, then drizzle caramel on top of cake. Finally, finish the entire cake by sprinkling MORE Butterfinger pieces on top.