take-out and prepared foods
Here are two obvious choices.
L'Appetito (875 N. Michigan, 2nd location at corner of Huron/Wabash)- an Italian deli literally at the base of the Hancock Tower. Their prepared salads and pastas are O.K., their sandwiches are wonderful. This will satisfy you, but is probably not suitable for your baby.
Whole Foods Market - 50 W. Huron (at Dearborn), probably a 10 or 15 minute walk from the Hancock. It has every kind of prepared food you could want.
The Treasure Island Mart (at 75 W. Elm) and Market (at 680 N. Lake Shore Drive,) are a little closer to the Hancock, but don't have quite as good a selection as Whole Foods, in terms of quantity and quality. IMO, of course.
I've been racking on my brain on this one - and it's a tuffy. If you were northside - I could name about 15-20 places, but the gold coast can be a wasteland where shopping for food is concerned. There's a Jewel food store at Division and Clark - but I seriously wouldn't suggest that. It's not nice. Oh! There's a Treasure Isle on Wells Street at North Avenue and that has a pretty good deli as far as take out is concerned. They've also got decent rotissere chicken and the ubquitiqous salad bar - there's a Treasure Isle closer but am unsure of it's quality, and they vary - radically. Personally I think Food Life in Water Tower is overrated and overpriced. I'm loath to eat or pick up food at some place with a "philosophy". I'll keep pondering this question and if I'm able to come up with anything I'll let you know. Pat Bruno at Brunoeats(AOL) may have more and better answers for you - he's the Sun Times food critic and lives and works in that area. He's always been very prompt and curtious regarding my E-mails to him. Hope this helps.