Preheat the oven to 350 degrees.
Line a 9x13 baking dish with foil and coat completely with nonstick spray.
In a large bowl, beat the butter, brown sugar and white sugar for about 2 minutes, or until light and fluffy.
Add in the eggs and vanilla, and stir to combine.
Add in the salt, baking soda, flour and cocoa powder, and mix until just combined.
Mix in the chocolate chips.
Press half of the cookie dough evenly into the baking dish.
Add the caramels and heavy cream in a medium sauce pan over medium heat. Heat caramels, stirring often, until they are creamy.
Pour caramel sauce over the cookie dough.
Drop remaining cookie dough over the caramel by the tablespoon.
Bake bars in the oven for about 30 minutes, until the center is just set.
Remove bars from the pan with the foil and cut and serve.
