This version streamlines the process into one bowl by melting the butter and chocolate together, so cleanup is minimal and no mixer is required. A quick chill after baking intensifies the cocoa flavor and firms the crumb, giving you sharp, bakery-style edges when you cut the squares.
Unsalted butter, melted ½ cup (115 g)
Preheat the oven to 350°F (175°C)
Chef’s Note: Stir 1 teaspoon of instant espresso powder into the warm butter-chocolate mix to deepen the cocoa flavor without adding noticeable coffee taste. Bake just until a toothpick shows a few moist crumbs; over-baking is what turns fudgy brownies cakey. Cool completely, wrap the whole slab, and let it rest overnight—the flavors bloom and the edges slice clean.