Spray a 9x13 baking dish with non-stick spray and set aside.
Start by making the caramel sauce.
In a small saucepan, heat butter until melted.
Whisk in brown sugar and milk. Heat over medium heat, bringing to a boil.
Boil for 5-6 minutes. Remove from the heat and stir in vanilla.
Place your caramel sauce into the refrigerator or freezer to cool.
In a large mixing bowl, combine brownie mix and the ingredients from the back of the box. Prepare according to directions. Pour the brownie batter into your 9x13 dish.
Once caramel has cooled slightly, begin making your caramel cheesecake topping. In a large mixing bowl, beat cream cheese for 1-2 minutes.
Add sugar, and mix again until incorporated. Add eggs and vanilla. Mix again until combined.
Add in caramel sauce. Mix one last time to combine the caramel with the cheesecake.