This is the very best brownie recipe you will ever find! It is dense, rich, chocolatey and perfect. You can half this recipe and put in a 9x13 pan if you don't want a cookie sheet.
Preheat the oven to 350 degrees. In a large mixing bowl add the butter. With an electric mixer, beat the butter until soft and smooth. Add the cups of sugar to the butter and continue to mix until all combined and white and fluffy. Add the cocoa powder and continue to mix until smooth. Add the eggs, salt and vanilla and continue to beat until the eggs are incorporated. Add the flour one cup at a time. Mix until combined. Spray a cookie jelly-roll pan with non-stick cooking spray. Pour the batter into the pan and level with a knife until smooth in the pan. Bake for 28-30 minutes, or until the center of the brownie seems stiff and no longer soft. However, you don't want to over bake the brownies! As they sit for a couple hours, they will harden and become the perfect, chewy texture. When they are finished baking, remove them from the oven and let them rest until ready to serve or frost. You can sprinkle them with powdered sugar, or top with a Buttercream Chocolate Frosting. Mint frosting is also great!