What is Chicago famous for?

Chicago deep dish pizza...yummmmm...

Tonight, in my last class (comprised of all middle-school girls), one of my students said, "Teacher, I have a question. What is Chicago famous for?" It's not every day that students show interest in learning about America, so this question really excited me. We had just finished reading a true story about a boy who fell into ice water after chasing his sled across Lake Michigan in January (he was pronounced dead at the scene, but after 20 minutes was revived). I mentioned to the students that I am from Chicago (well, close enough) and had explained to them what "sledding" is. Here in Sokcho, there aren't small hills like the ones we enjoy in the Midwest, and the lakes don't freeze. They were amazed to hear that in the U.S. there are lakes that freeze with ice so thick that you can drive on them!
But back to the question. I began to explain that Chicago is known as "the windy city," due to its proximity to Lake Michigan and the fresh breezes that come from there, before my student interrupted me to say "No Teacher--what food is Chicago famous for?"
Which led my mind to the 2 most famous Chicago foods I could think of: hot dogs and deep dish pizza. But you can actually find hot dogs in Korea (if you look hard enough), so I instead devoted my energies to explaining the phenomenon of deep dish pizza--the thick crust, the beautiful cheese and spinach (and sometimes sausage filling), the pie-like quality of this delight. By the end of the class all of our mouths were watering, and I wish I had a sample to share with them.
It's quite a small thing, I realize, but I was very pleased, for all of the energies we spend learning and investigating Korean culture, for the students to take an interest in ours.