
The hamburger's American story is a matter of friendly rivalry — from the Hamburg steak served to German immigrants in the 1800s to the 1904 St. Louis World's Fair, where one story says a harried cook slapped a hot patty between two slices of bread. What is certain: the cheeseburger became the emblem of the American diner, and a great one needs nothing more than a juicy patty, good cheese, and a toasted bun.