I need to backtrack slightly. Before we actually got to Chicago, we were in Omaha for a few days. Our hotel was very close to Wilson & Washburn and I'd heard amazing things about their beet burger.
Their take on this new classic is a seasoned beet patty with house smoked peanut butter + pickled jalapeño on a vegan bun. It does have a very strong beet flavor, but the pb and jalapeños really give it dimension. I loved the combination.