Soft butter, for greasing the pan
Flour, for dusting the buttered pan
4 large eggs
200g sugar, sifted
200g brown sugar, sifted
230g melted butter
105g cocoa powder, sifted
65g flour, sifted
1/2 teaspoon kosher salt
2 teaspoons vanilla extract
Preheat the oven to 300F/150C. Butter and flour an 8-inch square pan.
In a mixer fitted with a whisk attachment, beat the eggs at medium speed until fluffy and light yellow. Add both sugars. Add remaining ingredients, and mix to combine.
Pour the batter into a greased and floured 8-inch square pan and bake for 45 minutes. Check for doneness with the tried-and-true toothpick method: a toothpick inserted into the center of the pan should come out clean.
When it’s done, remove to a rack to cool. Resist the temptation to cut into it until it’s mostly cool.
TIPS
Whip your eggs until light and ribbony: Because this recipe doesn’t use any chemical leavening agents (like baking powder or baking soda), it’s important that you whip the eggs for long enough to incorporate air into them so your brownies have some lift. You want the eggs to be light yellow in color and thick, so be patient.
When checking the brownies for doneness, a little bit of wet crumbs stuck to the toothpick is OK: Unlike cakes, it’s OK if a bit of wet crumbs stick to the toothpick when you check them for doneness. It’s best to err on the side of underbaking these brownies versus overbaking them, so don’t wait until the toothpick is completely clean.
Allow the brownies to cool completely before cutting into them: If you try to cut the brownies too early, they will crumble apart and stick to your knife, so give them at least one hour to cool before attempting to cut them.