Mr. Beef doesn't have much atmosphere or seating room, but it's a much-loved Chicago institution. Its claim to fame is the classic Italian beef sandwich, the Chicago version of a Philly cheese steak. The Mr. Beef variety is made of sliced beef dipped in jus, piled high on a chewy bun, and topped with sweet or hot peppers. Heavy, filling, and very Chicago, Mr. Beef really hops during lunchtime, when dusty construction workers and suit-wearing businessmen crowd in for their meaty fix. While you're chowing, check out the celebrity photos and newspaper clippings covering the walls, and you'll see why this place is considered a local monument.