Before I tell you about the seasonally attuned courses the chef Hiroki Odo prepares at his new and virtuosic kaiseki restaurant, Odo, I want to tell you about some that he does not prepare. At two points during the March menu, a person who is not Mr. Odo faces you across the thick plank of Lebanon cedar that forms the dining counter and makes something for you.

The first time is about halfway through the meal, when Seong Cheol Byun shows up, shapes half a dozen pieces of sushi and lays them down, one by one, in front of you. Some of his ingredients, kept on wooden trays that he carries from place to place, are typical, like the warm short-grain rice and the dark nikiri that he will brush over certain fish. Others are less typical. The ginger he mounds on your plate is pickled together with sliced lotus root and daikon. On March 1, looking forward to spring, he added cherry leaves to the mix.

Mr. Byun, a Korean-American, ferments daikon, cabbage and sesame seeds to make white kimchi, which he wraps inside nori for a tuna roll. You eat it like an ice cream cone, but faster. When Mr. Byun worked at Sushi Nakazawa, much of the seafood he used was flown in from Japan. At Odo, almost all the fish have been caught off the East Coast of North America: Long Island black sea bass, Florida mackerel and North Carolina bluefin tuna, which may be several weeks old before Mr. Byun is ready to serve it.

This sushi reflects the American region where it is made, incorporates the Korean background of the chef making it and still has an unmistakably Japanese spirit. This one course, if tripled in length, could be spun off into a separate establishment that would probably be among the top two dozen sushi restaurants in the city.