Slugburger

A slugburger is a traditional Southern food originating in the area of Northeast Mississippi. John Weeks brought his hamburger recipe from Chicago to Corinth, Mississippi, in 1917. Weeks had local butchers grind his hamburger meat to specification, asking them to include potato flakes and flour. These small hamburgers were originally called Weeksburgers. Sometime before 1950, soy grits replaced the potato and flour. According to town legend, the term "slugburger" comes from the slang term for a metal disk the size of a nickel that would work in vending machines; the original price of the burger was a nickel.

Source: Wikipedia