Portillo's Restaurant Group, Inc. is an American fast casual restaurant chain based in the Chicago area that specializes in serving Chicago-style food such as hot dogs, Maxwell Street Polish, and Italian beef. The company was founded by Dick Portillo on April 9, 1963, in Villa Park, Illinois under the name "The Dog House". Outside of Chicago metropolitan area and Northern Illinois, the chain also has four locations each in central Illinois, the Indianapolis metropolitan area, and the Phoenix metropolitan area; three locations in the Minneapolis-St. Paul metropolitan area and Tampa metropolitan area; two locations each in the Milwaukee metropolitan area, Madison metropolitan area, Orlando, and Southern California; and one location each in Metro Detroit, South Bend metropolitan area, Fort Wayne, Dallas–Fort Worth metroplex, and the Quad Cities. From Wikipedia
