I wasn’t searching for a 50-year-old recipe for, of all things, a hamburger. It sort of leaped off the page, like my grandmother’s handwriting in the margins of a treasured book. The burger recipe, a James Beard gem, was published in House & Garden magazine in July 1956. During that year, Elvis Presley performed on the Ed Sullivan Show, the Yankees won the World Series, and Jif peanut butter was introduced to the home kitchen. Sledge hammers were fashionable cocktails at evening soirées, and backyard cookouts were all the rage in suburban America.