French chefs compete for 'best burger' title Hazelnut buns, frogs' legs, and, of course, plenty of butter -- these are a few of the ingredients chefs from five French regions hoped would set their best burgers apart and earn them the Coupe de France du Burger. The competition comes just as burger sales in France soar higher than the classic jambon-beurre baguette for the first time in history. IMAGES AND SOUNDBITES