Walls’ “Big Square Burger” is indeed square, but it isn’t really huge. It is a modest-sized patty, available in the “Big Square Box” configuration, which means fully dressed with French fries and baked beans on the side. If you really do have a big appetite, you can get a double-size square burger or, better yet, a “Wall Banger Special,” which is a Big Square topped with melted cheese and a round of Canadian bacon.