Preheat oven to 350 F degrees and adjust oven rack to the lower third position. Lightly spray an oven safe 9 inch skillet with cooking spray and set aside.
Add butter and chopped semi sweet and milk chocolate to a large microwave safe bowl and microwave in 20-30 second increments, stirring after each increment, until melted. Set aside for 5-10 minutes to cool slightly.
Add whisked granulated sugar to the chocolate mixture, then add eggs and vanilla, whisking until smooth.
Add flour and cocoa powder and fold in gently, just until no streaks of flour remain. Stir in 1/2 of the chopped Hershey bar and 1/2 of the chopped rolo candies.
Pour brownie batter into prepared skillet, sprinkle remaining chopped Hershey bar over the top of the batter, and bake for about 30 minutes. To check for proper doneness, insert a toothpick in the center. When it comes out with a few moist crumbs, it's done.
Let brownie cool for 5-10 minutes, top with leftover chopped rolo candies, a scoop of ice cream (if desired) and drizzle with salted caramel sauce. Grab a spoon and dig in!