Chicago-style relish is a type of sweet pickle relish typically used on

Chicago-style hot dog A Chicago-style hot dog, Chicago Dog, or Chicago Red Hot is an all-beef frankfurter on a poppy seed bun, originating from the city of Chicago, Illinois. The hot dog is topped with yellow mustard, chopped white onions, bright green sweet pick ...

s.Zeldes, Leah (July 20, 2010)
"Origins of Neon Relish and Other Chicago Hot Dog Conundrums"
, ''Dining Chicago''. Retrieved July 19, 2016. The unique color of the relish, often referred to as "neon green", is created by adding blue dye to regular pickle relish. The first use of Chicago-style relish on a hot dog has been attributed to several different restaurants, including

Fluky's Fluky's is a Chicago-area fast food restaurant and mail-order food purveyor known for hot dogs."Fluky's History"

and Superdawg.

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