Preheat oven to 325°F and line a 9×13 inch baking pan with aluminum foil. Coat foil with non-stick spray.
Combine the sweetened condensed milk and unwrapped caramels in a medium sauce pot and place over medium-low heat. Stir frequently until the caramels melt and the mixture is smooth and a medium-dark amber color. Set aside.
In a medium bowl, combine flour, baking soda, and salt and mix together.
In a large bowl or mixer, beat together butter and sugars until combined. Then add eggs one by one, mixing after each addition.
Add in vanilla extract, then gradually mix in dry ingredients until just combined.
Fold in chocolate chips, then press half of the cookie dough into foil-lined baking dish.
Pour the caramel mixture over the cookie dough, and spoon the remaining cookie dough over the top taking care that the spoonfuls are evenly distributed across the whole dish.
Bake for 25-30 minutes, or until golden brown and the edges have begun to pull away from the sides of the pan.
Remove from oven and let cool completely. Lift bars out of pan by the edges of the foil and cut into bars. Serve and enjoy!