Engineered for dense fudge texture with no cakiness. High-fat butter emulsion and dissolved sugar foam produce that elusive paper-thin meringue crust.
Preheat oven to 350°F (175°C). Line an 8x8-inch metal baking pan with parchment paper, leaving an overhang on opposite sides. Melt the 170g butter until bubbling hot. Whisk in the 85g cocoa powder until completely smooth. Blooming cocoa in hot fat dissolves flavor compounds and amplifies chocolate intensity.
In a separate bowl, whip 150g eggs and 260g sugar with a handheld mixer on high speed for 3-4 minutes until pale, thickened, and doubled in volume. Dissolving sugar in egg proteins is the secret mechanism behind the paper-thin crinkly crust.
Slowly drizzle the warm cocoa-butter mixture into the whipped eggs while beating on low speed until completely combined and glossy.
Gently fold in 70g all-purpose flour and 3g salt with a rubber spatula just until combined. Gently fold in 120g chopped dark chocolate chunks.
Pour batter into the prepared pan and smooth the top. Bake for 26-29 minutes. A toothpick inserted into the center should come out with moist fudge crumbs, never raw liquid batter and never completely clean.
Let cool in the pan on a wire rack for at least 2 hours. Chilling in the refrigerator for 1 hour produces razor-sharp, bakery-style squares.
The Crinkly Skin Secret: The shiny crinkled skin on brownies is not created by chocolate, but by dissolved sucrose migrating with egg albumin to form a micro-meringue during baking.
Low Gluten Formation: With only 70g of flour to 170g of fat, gluten development is almost zero, guaranteeing a dense fudge texture instead of a sponge cake.
Use our calculator to convert custom quantities or alternative flours for this recipe.
Technique note: Fluff flour with a fork, spoon gently into the cup until heaping, then sweep level with a straight edge. Never scoop directly.
Verified standard: 1 US cup of All-Purpose Flour = 120 grams (King Arthur Baking & USDA FoodData Central (FDC ID: 168936)).
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