In your mixing bowl, beat together the melted butter and sugar until creamy.
Add in the eggs, vanilla, and salt. Beat until combined.
Add in the flour and baking cocoa and mix until combined. This batter will be thick. Be sure to scrape the bowl with a rubber spatula to get it all mixed together well.
Spread the batter into a 9x13 baking dish that has been lined with parchment paper.
Bake for 35 minutes.
Allow the brownies to cool for 10 minutes in the pan. Lift the brownies from the pan by grasping the parchment paper and transfer it over to a cooling rack. Cool completely before cutting.