A patty melt is traditionally served on what type of bread?

A patty melt is traditionally served on rye bread.

Unlike a classic hamburger, which is usually placed in a soft round bun, a patty melt is built between two slices of griddled bread. The traditional bread is caraway-seeded rye or marbled rye, whose savory flavor pairs especially well with beef, melted Swiss cheese, and sweet caramelized onions.

The sandwich sits between two familiar categories: it can resemble a cheeseburger because of its beef patty, but it is prepared more like a grilled cheese, with buttered or oiled bread toasted on a flat-top grill. Sourdough and Texas toast are common substitutions, but they are variations rather than the classic choice.

The patty melt’s exact inventor is uncertain. Los Angeles restaurateur Tiny Naylor is often credited with popularizing it, and the sandwich appeared at Tiny Naylor’s restaurants by the early 1950s. It is also commonly confused with a hamburger on toast, but the grilled bread, onions, and cheese are defining features of the style.