You need to learn the Google! :-)
First try came up with this:
Date: June 25, 2007
Foodies note: Unlock the "secret" Japanese menu at Itto Sushi
Posted by Monica Eng at 5:45 p.m. CDT
As a lot of curious local foodies have learned that plenty of ethnic restaurants harbor secret menus for people from their own culture, not so much because they're being exclusionary, but because they don't want to freak out less-adventurous diners with dishes restaurateurs think they will find too prosaic, too esoteric or too scary.
Over the last couple of years, LTHForum has translated a bunch of Thai and Chinese menus around town and metromix.com offered a round-up of a few of these spots.
We recently discovered such a "secret" menu at Itto Sushi, one of Chicago's oldest Japanese sushi houses and one of the few that is actually Japanese owned and run. I mentioned to co-owner Keiko Hatori (wife of sushi chef Juco Hatori) that sometimes I have a hankering for a good onigiri (like a handheld triangular maki sandwich with a bit of fish or pickled plum inside) or a creamy chawanmushi (rich savory custard), but can rarely find them in the city.
She responded by showing me the Japanese menu which features both of those items along with dishes like the less appetizing (in my book) sticky fermented soybean called natto ($4) and a rice and tea soup called ochazuki for $5.95. One onigiri costs $2.75 and a chawanmushi goes for $6.75.
Another interesting fact about Itto that we discovered during our visit there is that regulars can help save the trees (albeit in small way) by keeping their own laquered chopsticks there boxed up, labeled and ready to use every time they dine.
Itto Sushi, 2616 N. Halsted St.; 773-871-1800
I know the google quite well enough, thanks. However, I was a bit unclear in my original post. Restaurant onigiri -- t'uh! Has to be from a store, preferably a convenience store. Just like I did it in Japan! Half the fun is putting the nori on oneself and waiting for the exactly perfect moment to start eating. Thanks for your post anyway. Mitsuwa says they carry some, so I'll be swinging by to check it out and get a dose of nostaligia (more than I can here in Mpls).