Prepare your cake as directed on box in a clear 9x13" baking pan
Let cool and poke holes in the top of your cake with a spoon handle
Mix together your sweetened condensed milk and caramel
Pour your caramel mix over the top of your cake
Let set for 15 minutes
Frost with your tub of cool whip
Pour half your bag of Heath bits over your cool whip
Slice and enjoy!