JeffB wrote:But I do think in Cleveland and Pittsburgh both pierogies and paczki (what I think of as the basic ethnic Polish foods people know) approach the broad popularity they enjoy here. Not nearly as many Poles, of course, but Poles (and people of Polish ancestory) as a percentage of the population, it might be pretty close. At P'burgh sporting events, they have pierogi races.
I recently escorted some foodie visitors from Cleveland to what I think of as a fairly routine Polish deli here and they were in raptures. They particularly commented on the paczki: "Oh, I thought those were only for Fat Tuesday!"
But I don't know Cleveland or these folks well, so I can't tell if they've just been unobservant at home.
Paczki are certainly more widespread than hot links, but you'd have trouble finding them in, say, San Francisco, or Cincinnati. So although we might share them with some other places, they're certainly part of Chicago's culinary tradition.
Another example of a Chicago ethnic food could be Italian lemonade. You can find it up and down the East Coast, I believe, but I never heard of it before I moved to Chicago and I'm sure you can't get it in Detroit, whereas here it's part of the culture of the city. I remember one of the TV stations used to shut down every night with a sequence of familiar city scenes, including a crowd lined up at Mario's.
From the opposite end, I'd call avgolemono a Detroit food in a way that it isn't a Chicago food. You can get it in any Greek restaurant here, and most people probably know what it is, but in Detroit you're apt to find it at any routine diner or hot dog stand (or at least you could when I was growing up there). To be sure, the diners are mostly run by Greeks, but similar places here don't usually have it.
Does this make sense?