These days in and around Chicago, the vast majority of our fine dining and finer dining restaurants are open on Sundays; that's hardly a big restriction! Opentable.com accepts reservations for 316 of the nicer restaurants in the city; I just checked a few weeks from now and found that 252 of them have availability on a Sunday evening, including many of the highest-end places: NoMI, Spiaggia, North Pond, TRU, Sixteen, L2O, Bonsoiree. Even Alinea (which does not use Opentable) is open on Sundays. If you would like something closer in price to Graham Elliot than those pricier places, consider Cafe des Architectes, Mercat a la Planxa, Mexique, Cafe Spiaggia, Spring, or Sweets and Savories.