Prep your pan and oven
Preheat oven to 175°C / 350°F. Grease or line an 8×8-inch baking pan with parchment paper. Future you will thank you for the easy cleanup.
Melt butter and mix sugar
In a medium saucepan, melt butter over low heat. Remove from heat and stir in sugar until glossy and smooth. It should look like liquid chocolate happiness.
Add eggs and vanilla
Whisk in eggs, one at a time, then stir in vanilla. Yes, it smells amazing already.
Combine dry ingredients
Sift together cocoa powder, flour, salt, and baking powder. Gently fold into wet mixture until just combined. Do not overmix—fudgy > cakey.
Add extras
Fold in chocolate chips or any add-ins. Resistance is futile.
Bake
Pour batter into prepared pan and bake for 20–25 minutes. Edges should be firm, centers slightly soft (they’ll set as they cool).
Cool and slice
Let brownies cool completely (if you can wait). Slice into squares and brace yourself for compliments.