A chocolate brownie is a flat, baked square or bar introduced in the United States at the end of the nineteenth century and popularized in both the U.S. and Canada during the first half of the twentieth century. The brownie is sliced from a type of dense, rich chocolate cake, which is, in texture, like a cross between a cake and a cookie. Brownies come in a variety of forms. They are either fudgy or cakey, depending on their density, and they may include nuts, frosting, whipped cream, chocolate chips, or other ingredients. A variation that is made with brown sugar and no chocolate is called a blondie.

Brownies are common lunchbox fare, typically eaten by hand, and often accompanied by milk or coffee. They are sometimes served warm with ice cream (à la mode) or topped with whipped cream, especially in restaurants.