Cover a small cookie sheet with parchment paper; set aside.
Unwrap and slice the Rolos in half.
Place 1-¾ cups of the Rolos on the cookie sheet and place in the freezer.
Pre-heat the oven to 350°F.
Line a 9 x 9-inch baking dish with a parchment paper sling; set aside.
Using a small mixing bowl, whisk together the flour, cocoa powder and salt; set aside.
Using a medium-sized, heat-safe mixing bowl, combine the dark chocolate chips and butter.
Microwave for 1 minutes, stir; heat in 15-second intervals until the mixture is melted and smooth.
Add the brown and white sugars to the chocolate mixture; continue stirring until incorporated.
Stir in the eggs, one at a time, until no egg streaks are visible; stir in the vanilla.
Stir in ½ of the flour, cocoa powder and salt; stir until combined; add the remaining flour, cocoa powder and salt mixture; stir just until all the flour mixture is incorporated; do not overmix.
Spoon ½ of the brownie batter into the prepared pan; spread the batter to the edges of the pan.
Evenly place the frozen Rolos over the batter.
Spoon and spread the remaining batter over the top of the Rolo layer.
Place in the pre-heated oven and bake for 25 - 30 minutes or until a toothpick inserted comes away clean.