One caveat comes with this hot dog haven: The service is usually slow. Perhaps that's part of the shtick, though: Much of Fat Lou's appeal is in its big-city ambience and the high-minded way it has elevated itself above the mundane, no-frills hot dog stands that dot our suburbs. By contrast, Fat Lou's is a bona fide hot dog restaurant, with booths, tables, beer on tap, TVs all over the place tuned to the Cubs, White Sox, Bears, or Bulls, and plenty of room to stretch out. Though Fat Lou's does a stellar job of presenting its Chicago dog -- a steamed red-hot with relish, yellow mustard, peppers, celery salt, and tomatoes, it also offers a decent take on a classic New Yawk hot dog, with grilled red onions, sauerkraut, and brown mustard. Do not, under any circumstances, miss out on the Italian roast beef sandwich, a Chicago tradition that's served au jus and with giardiniera (pickled veggies) on a huge roll that's as messy as it is satisfying. You may have to rest your elbows for a while as your order is prepared, but the rewards are ample, and at least you won't be bumping elbows with the lunch crowd in some cramped stool 'n' counter joint.