Prepare brownie mix as directed on the box. Heat oven to the temperature recommended on the box.
Spray a 9" X 9" baking pan with non-stick spray. Alternately you can use parchment paper if you want to lift the brownies out to cut them instead of cutting them in the pan.
Chop up the Snickers bars into ½ inch pieces.
Pour half of the prepared brownie batter into the baking pan.
Bake for 6 minutes then remove from the oven.
While the bottom layer of brownies are baking, add caramel bits and heavy cream to a bowl and microwave in 25 second increments, stirring in between until melted. Make sure not to overheat and burn the caramel.
Sprinkle the pieces of snickers bars evenly over the semi-baked layer of brownies. Then drizzle the melted caramel all over the Snickers bar pieces.
Pour on the remaining batter. Make sure to pour all over the surface area so that it spreads easily. Use an offset spatula to evenly spread the brownie batter over top of the whole pan.
Bake for the remaining amount of time recommended on the box mix instructions.
Check the brownies for doneness, then remove from the oven.
Let the brownies rest in pan before cutting.