A hamburger is a sandwich consisting of a ground meat patty, usually beef, placed inside a sliced bun. The patty is often pan fried, barbecued, or flame broiled. The term "hamburger" originated from Hamburg, Germany, and the word "burger" now refers to various meat or meatless sandwiches. To prepare a hot hamburger sandwich, assemble the ingredients like the bun, cheese slices, vegetables, cooked patty, and condiments. Toast the bun and build the sandwich by layering the ingredients before placing it in the oven to heat through.