The regional Mississippi burger made with a beef patty, mustard, onion, and a steamed bun is called a slugburger.
Slugburgers originated in northeastern Mississippi, especially around Corinth, during the early twentieth century. The patty traditionally combines ground beef with a cereal extender, historically commonly soybean meal, breadcrumbs, or another inexpensive filler. This made a small portion of meat more affordable during periods when food budgets were tight.
The name is linked to the “slug,” a slang term for a five-cent coin. The burger was therefore associated with an inexpensive meal rather than with the animal commonly called a slug. Modern versions may be larger and may use different proportions of beef and filler.
A classic slugburger is often fried rather than cooked like a thick restaurant hamburger. Mustard, onions, and pickles are common accompaniments, and a soft bun completes the sandwich. The recipe varies by restaurant, but the economical beef-and-extender patty is the key historical feature.