Thinly sliced fried slabs on white toast became widespread on menus in St. Louis, Missouri, after the rise of the city's stockyards in the late 1880s, although demand there has so dwindled that only a handful of restaurants still offer them.
They remain popular in the Ohio River valley, where they are served heavily battered on hamburger buns.
In Evansville, Indiana, they are still offered at several "mom and pop" eateries.
[1] Brains from cows over 30 months old at slaughter are no longer permitted to be sold for human consumption in the United States.
[2] Some restaurants have taken to serving pigs' brains instead of cows' brains due to concerns regarding bovine spongiform encephalopathy, commonly known as "mad cow disease".