How simple. How healthful. How easy to like, even for those few souls who haven't been initiated into the ways of sushi. The California roll--tuna, avocado, rice and a light coating of roe--is sort of a basic building block of American sushi dining. This is starter sushi, as much American as Japanese. Some would say it's passé, but not us. If it's over, then prime steak was out after 1966. (Actually, it was, but it hid in the mountains like a patient guerrilla fighter.) Same with the California roll. At this solid, unpretentious and thoroughly popular sushi palace, they make this old standard flawlessly. The flavors meld and blend in your little puddle of soy sauce. Start here, then work deeper and deeper into the dining ways of the Far East.