Preheat the oven to 350 degrees.
Spray the pan with non-stick cooking spray, set aside.
Start with the box mix, add the butter and milk, mix to combine.
Add the eggs, one in a time - mixing between each addition.
Bake as directed according to the package directions.
Remove from the oven and while it's warm, using the end of a wooden spoon poke holes all over the cake.
Remove the cake from the oven, immediately poke holes over the entire cake. I used the handle of a wooden spoon.
Pour the sweetened condensed milk over the top of the cake.
Next drizzle three fourths of the caramel sauce over the cake.
Allow to cool on the counter for an hour to room temperature. Refrigerate for two hours.
While it's chilling, chop the candy bars into small bits.
Remove the cake from the refrigerator, top with Cool Whip, drizzle with chocolate and remaining caramel.
Sprinkle with candy bits!
Serve and seriously enjoy! Cover with plastic wrap, refrigerate leftovers.