Chicagoans take hot dogs very seriously, and for a good reason: you can't get 'em better in any other city. And while Chicago's best restaurants may try their hand at something more gourmet, fancy or artistic, nothing beats an old-school hot dog stand. The sausage capital of America keeps on offering a smattering of excellent hot dogs dragged through the garden (we'll explain what that means :)) with toppings... and be careful... the ketchup is only for the fries.
A Chicago-style hot dog, Chicago Dog, or Chicago Red Hot is an all-beef frankfurter on a poppy seed bun. The hot dog is topped with yellow mustard, chopped white onions, bright green sweet pickle relish, a dill pickle spear, tomato slices or wedges, pickled sport peppers and a dash of celery salt. The complete construction of a Chicago hot dog is said to be "dragged through the garden" due to the many toppings; the method for cooking the hot dog itself varies depending on the vendor's preference: you can find them steamed, water-simmered, or less often grilled over charcoal (in which case they are referred to as "char-dogs").
The official recipe does not include ketchup, and there is a widely shared, strong opinion among many locals and Chicago-style hot dog lovers that ketchup is unacceptable. Some of Chicago hot dog vendors do not even offer ketchup as a condiment.
The founders of Vienna Beef frankfurters, the most common brand served today, first sold at the 1893 World's Columbian Exposition in Chicago, and the proprietors of Fluky's were both Jewish, which might be the reason why the wieners are pork-free, kosher-style like.