I lived in Chicago for 10 years. I have also live in multiple east coasts places, Cali, and Colorado. Nothing could ever come close to a true deep dish. Why? Its bread, sauce and cheese, There was a place in san diego(wtf) that was very close, but the restaurant which I cant remember was run by some old chicago people. The only thing I can think of is people in chicago realize its going to take 45-60 min to make a pizza, outside of chicago no one is willing to wait that long nor is a restaurant willing to have customers idle that long.