Need to Know
Whisking cocoa powder into melted butter—instead of stirring it in—helps break up any lumps for a smooth brownie batter.
Cocoa choice This recipe calls for natural unsweetened cocoa powder, which has a much stronger chocolate flavor than melted bittersweet chocolate. (Cocoa powder is chocolate with most of its cocoa butter pressed out, hence its big chocolate punch.) Don’t substitute Dutch-processed cocoa; it has a milder flavor and so will your brownies.
Pan pick For brownies with sharp, clean edges, use a straight-sided rectangular metal baking pan and line it with aluminum foil for easy brownie removal. The foil also helps with cleanup.
Temp test Once you’ve combined the hot melted butter with the cocoa, sugar, and salt, check the batter with your fingertip before adding the eggs. It should be warm—not hot—or your eggs will cook and curdle. Set it aside to cool for a few minutes if necessary.