What is your price range? Are you willing to travel from the general area of the Hyatt? Are you interested in any particular type of food or dining experience? Do you require a reservation, or are you willing to deal with a potentially inconvenient wait?
As far as price, I don't care - nothing too crazy because of who I'm with. I know they all like steak and most of them drink so anything with that combo is good. I doubt any of them brought more than standard coaching attire though so that needs to be considered.
Quartino's (see link). It's very casual. You order small plates. You start with two or three, and everyone takes a portion. Eat, drink and talk. As you finish them, order more. Click on the link, then go to menu to see some pictures. You won't be disappointed.
It's too cold to walk. So, take a cab.
...connecting about half a dozen buildings. There are a lot of quick-food places in there, plus one or two decent sit-down restaurants. The plus side is not having to go outside to reach them. If you want steak, there are at least a dozen places within short cab/walking distance, mostly just across the river and heading north. If you use Google maps and enter "steak restaurants downtown Chicago" you will see them all with clickable links for reviews and websites. With reference to the map, you'll be at the SEC of Michigan and Wacker on the immediate south side of the river.
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