Culinary historians have traced the first cake “brownie” to the 1906 edition of The Boston Cooking-School Cook Book, edited by Fannie Merritt Farmer. This recipe is an early, less rich and chocolaty version of the brownie we know today, utilizing two squares of melted Baker’s chocolate. Food historians don’t know if Fanny Farmer obtained the recipe from another source, printed it as is or adapted it, or provided the name.
The second recipe, appearing in 1907, was in Lowney’s Cook Book, written by Maria Willet Howard and published by the Walter M. Lowney Company of Boston. Ms. Howard, a protégé of Ms. Farmer, added an extra egg and an extra square of chocolate to the Boston Cooking-School recipe, creating a richer, more chocolaty brownie
Be sure to test for doneness before removing the brownies from the oven. If underbaked (the toothpick has batter clinging to it), the texture of the brownies will be dense and gummy; if overbaked (the toothpick comes out completely clean), the brownies will be dry and cakey.