Preheat your oven to 350°F (175°C). Grease and line a 9x13-inch baking pan with parchment paper.
In a saucepan, melt unsalted butter over medium heat. Remove from heat and stir in granulated sugar until well combined.
Add eggs and vanilla extract, beating well.
In a separate bowl, whisk together all-purpose flour, cocoa powder, baking powder, and salt.
Gradually add the dry ingredients to the wet ingredients, stirring until just combined.
Pour the brownie batter into the prepared baking pan, spreading it evenly.