Preheat oven to 350°F (175°C). Grease and flour an 8x8 inch baking pan.
In a medium bowl, whisk together flour, cocoa powder, and salt.
In a large bowl, whisk together melted butter, granulated sugar, and brown sugar until combined. Beat in eggs one at a time, then stir in vanilla extract.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined. Be careful not to overmix.
Pour batter into the prepared pan and bake for 25-30 minutes, or until a toothpick inserted into the center comes out with a few moist crumbs.
Let the brownies cool completely in the pan before cutting into squares.
Video
Notes
For extra fudgy brownies, slightly underbake them.You can add mix-ins like chopped nuts, chocolate chips, or espresso powder for extra flavor.