Frank had to do some research to prove to Jerome that what Americans call French onion soup really is from France. Jerome never saw it when he was growing up. He and the soup apparently come from different regions. We caramelize three types of onions—yellow onions, red onions, and leeks—to make this sweet, hearty soup. At the store, we don’t do the whole melted-cheese top thing that characterizes French onion soup, so we didn’t think it deserved that name. Three-onion soup is even better the next day. Serve it with French bread, of course. Click for recipe