John Hong

Mr. Hong, who grew up in Los Angeles and trained under sushi master Yukio Sakai, decided the concept was worth gambling on in San Diego. He opened Hidden Fish in September, offering 30-minute and 90-minute meals, and very quickly had to make an adjustment.

“In California we’re pretty laid back compared to New York, and I saw so many comments from people who were like, ‘Why would I want to eat in 30 minutes?’” he says with a chuckle. “So we made it 50 minutes.”

At Hidden Fish, which bills itself as the city’s first timed omakase experience, there are no maki rolls, no hot appetizers, no soups and no dessert. Fifty-minute diners receive 12 pieces of nigiri; 90-minute diners get 18. An à la carte menu of hand rolls, nigiri and specialty nigiri (like toro with uni, black truffle and sturgeon caviar) is available for those still hungry at the end of their meal.

At least 60 percent of Mr. Hong’s fish comes from Japan, with the rest sourced from Canada, Scandinavia and local fishermen. The menu changes each morning based on what’s available. On a recent evening, as Mr. Hong knocked back beers and his two apprentices asked shyly if they could accept the sake offered them by a guest, diners were served a pristine golden eye snapper garnished with lemon zest; a fatty salmon with a dollop of yuzukosho — a paste of chilies, yuzu peel and salt; and a bright orange wad of local uni, served on a square of nori with glistening salmon roe on top, which Mr. Hong instructed diners to “pick up and eat just like a taco.”

In San Diego, where the California roll still reigns supreme, Mr. Hong says he knows he has to be careful with how much he pushes his guests.

“The hardest part is planning the daily menu,” he said. “I’d love to play with live abalone, or serve fresh live octopus. But there are people who would get scared off by that. It’s all baby steps.”