If you think you know Japanese cuisine, get ready to be schooled by Ohshima. At this sushi bar that looks like any other from here to Peoria, you'll likely see foods you've never even considered putting in your mouth. Somewhere between the pig's ear salad and the barracuda sushi, it dawns on you how little you know. One way to start the lesson is to do omakase; ask Shige, your chef/guide/teacher, to give you what his Japanese clients would order. For hot dishes, just look at the specials. Order the bitter melon salad—it will send the message that you aren't just there for the teriyaki and are ready to start learning.