Hamburgers invade Paris

Beginning a few years ago but picking up momentum in the past nine months, hamburgers and cheeseburgers have invaded the city. Anywhere tourists are likely to go this summer -- in St.-Germain cafes, in fashion-world hangouts, even in restaurants run by three-star chefs -- they are likely to find a juicy beef patty, almost invariably on a sesame seed bun.

"It has the taste of the forbidden, the illicit -- the subversive, even," said Hélène Samuel, a restaurant consultant here. "Eating with your hands, it's pure regression. Naturally, everyone wants it."

"A hamburger is the architecture of taste par excellence," she explained. "The meat needs to be a mix of fatty and lean. Not raw, not rare. It must be medium rare. At the same time the bread needs to be smooth, tepid, toasted on the sesame side. I like to brush the soft side with butter. There needs to be a crispy chiffonade of iceberg lettuce. Everything plays a role."