For weekend lunch in Evanston, it's hard to beat Lulu's all-you-can-eat deal. Big plus; it's not a buffet. For under $15 you get free reign of the menu (with just a few exceptions). Pan-Asian salads, entrees, dim sum, noodles, etc. No, it's not wholly "authentic," but generally enjoyable. Go to joy Yee's--even if it's just for a bubble-tea. They offer a staggeringly large selection of bubble-teas and other fruit-based drinks. Unlike other many other bubble-tea shops, most of Joy Yee's are made with fresh fruit. There must be a couple hundred drink variations on their menu! The other food is variable, but generally good (and very cheap, given the HUGE portions). The only drawback is the extreme noise level and cramped tables. But, oh those drinks! Most of the higher-end places like Va Pensiero, Campagnola, Stained Glass, Oceanique don't serve lunch. The major exception, as mentioned earlier, is Trio's Friday-only affair. Although lunch is just a tiny "trailer" for the Grant Achatz show; it's still a blast. With wine and extras, however, this can become a $100/person lunch. Finally, if you like to cook, try to get to the Spice House. It's a mile or two from downtown, but has an unbelievably amazing selection. Best spice strore I've ever seen (so much so that the CIA at Greystone sells their products). For spending an entire day, I think you'd enjoy downtown Evanston a lot more than Rogers Park.