Method
Heat the oven to 350°F. Line a 9-by-13-inch pan with parchment.
Whisk melted butter, sugar, and cocoa. Add eggs one at a time, whisking well, then add vanilla.
Fold in flour and salt just until no dry streaks remain, then fold in chocolate if using. Spread evenly in the pan.
Bake until the edges are set and a tester near the center has moist crumbs, 25–32 minutes. Cool completely before cutting.
Notes
Overbaking is the usual cause of cakey, dry brownies. Confirm cottage-food eligibility locally before sale.
Related recipes and techniques
These are extensions, technique comparisons, or serving relationships; the complete recipe above remains usable as written.
- For a portioned chocolate bake, see Chewy Chocolate Chip Cookies.
- For a lighter-crumb chocolate dessert, see One-Bowl Chocolate Cake.