Chinatown, a few miles south of the Loop. I know, it sounds like a joke, but it's not. None of the places in the vicinity of Evanston has consistently impressed me, and when I want really good Chinese food, I go down to Chinatown.
However, of the ones I've tried in and around Evanston, the best one I've found is Koi, in downtown Evanston ( www.koievanston.com ). I've had several dinners there; sometimes it has actually been very good, but other times, it's been less so. What I like about it is that they're not afraid to make dishes spicy, and also, the portion sizes are quite large, thereby offsetting the somewhat high prices there. So when I want Chinese and I don't feel like going all the way to Chinatown, I go back to Koi.
Whatever you do, don't bother with Pine Yard; it's dreadful.
I'm open to other suggestions, so if anyone can suggest another place in the area, please do!