out in Maywood or Melrose Park? (I forget which suburb it's in). That's the place with a stuffed polar bear in a revolving glass cylinder over the front door, and inside over the stone fireplace they have 1/2 of a moose, and the other side of the fireplace has the other 1/2 (I know which side I preferred to look at!) They had great 1/3 pound burgers and plenty of midwestern beers on tap.
Or out in Downers Grove many years ago was a place called the "Beef 'N Barrel" that had a "Belly Buster" - two 1/2 pound patties on a double decker bun. If you ate one in one sitting without hurling, you got a certificate of achievement. Once a year they had a contest to see who could eat the most in (I think) an afternoon. HS football players used to go in, scarf them down, run to the men's room and hurl, then come back for more. Can't remember what the grand prize was, though.
God, I miss Chicagoland!