There hasn't been an updated review of this place in a while. Since there was a request for one, plus I had wanted to put in an update, so here it is!
Sushi Kuni on the outside looks like a very cozy cottage. It is in the complex where Radio Shack is (in fact right next door) just a few short minutes drive from Apple. In fact you see lots of Apple employees eat there. The restaurant also attracts the Chinese/Taiwanese crowd who shop at Marina Supermarket nearby.
The chef owner's name I believe is Kunio, and he's always on the side of the counter closest to the kitchen. He's a really nice guy, doesn't chat much but can go on if you start or if he wants to make conversation with you! His assistant, I believe is Steve is also a master with the knife and also does nigiri and rolls.
I've never had cooked food there, except for one or two dinner appetizer items, and it has been a while so I will probably not include those in this review.
Sushi Kuni has come quite a long way from my first visit back in 2003 or so, till now. I remember I was not blown away by my first visit, but have given them a 2nd chance and started to come back many times ever since.
They offer the standard sushi items that are also on the menu. They do have specials every now and then, which are tai (red snapper, from New Zealand), kohada (gizzard shad), aji (spanish mackeral), and lately they been offering suzuki (sea bass), mirguai as well.
Bottom line is variety is not huge like the high end places, but overall the quality is pretty sweet for the area.
Some highlights and favorites:
Hirame - Stands out on its own without additional flavoring. Many restaurants have decent hirame, but they need that extra dash of ponzu sauce, green onions and minced marinated ginger. Sushi Kuni's offering is very meaty and chewy, great texture and natural flavor, but all in a good way.
Aji - They don't always have it, but it is one of the softest and freshest pieces around. Nothing fancy, but straight up fresh, tender. If you try this on the day that he gets it in, it is as good as the top end restaurants.
Anago - I learned that Kunio-san prepares his own anago, which is a plus! This is a very tender cut, and literally melts in your mouth smoothly. Many sushi bars do not do anago well, either the type of sea eel they use is coarse with meat texture, or they cook it too long and it ends up being dry and chewy, or use of a frozen aged source. Kunio-san said that the anago he uses is sourced to either Japan or China.
Sushi Sam's in San Mateo does a nice anago, but the price is much higher. Sakae's anago is insanely sweet and decadent, especially the Japanese anago when it is on the white board, but that's really hitting the 2 digit price line. Sushi Kuni's is not only very tasty, but a very reasonable $4.
Salmon - I'm not a huge fan of salmon for sushi, but lately I've been having it again and also at Sushi Kuni. It is not a super fatty cut, but the way it is prepared is very nice. The salmon is apparently kept in deep freeze for some time, thawed, then brined. I don't know how Kunio san does it but it tastes almost like a different fish. Most of the regulars that I see also order this, and apparently the Japanese expats like this too.
Kohada - well it is not a fantastic version, but it is not bad. (Better kohada, when available can be found at Sushi Tomi and Kitsho). But one thing deserves great mention; I've been noticing that before Kunio-san used to prepare kohada from pre-marinated and pre-made packets/containers (sourced to a vendor), but about a month ago he started marinating his own from scratch! If you go on Tuesday or Wednesday, you might even see the kohada cut in half, sprinkled with salt and letting it sit to marinate.
Hotaru ika - This is a very limited seasonal offering, and just recently had it this past week. For those who don't know this is raw baby squid. It is served either as sashimi (request) or in sushi form via gunkan (battleship) like how uni or ikura is usually served. Kunio-san added a little bit of minced regular ginger, plus a mildly sweet sauce over it. I don't think it was miso, but I do know Sushi Tomi and Sushi Sam's use a sweet miso sauce when they serve hotaru ika. Fantastic stuff. Once in a blue moon, you'll find hotaru ika at Nijiya or Mitsuwa supermarkets, but no sauce comes with it ;-).
While Sushi Kuni is not earth shattering like the high end places and does not have a wide spectrum of fish varieties (though decent enough), it is definitely a good neighborhood sushi bar.