LAS VEGAS—As an experienced bartender, Russell Gardner knows all too well what many beer drinkers want—a frosty mug and a ready pour of a mass-market brew. And he concedes that it doesn't exactly take an advanced degree to provide such no-frills service.

Still, Mr. Gardner, a manager at a recently opened gastro pub here, has that very certification. Meaning he's proud to call himself a Cicerone. A what?

"It's...