The site's ranking was determined by millions of user reviews.

Every year, the online booking site TripAdvisor mines its millions of user reviews to name the best restaurants and travel experiences in America and around the world. This month, the site announced its ranking for the fast-casual restaurants in the country, which drew from TripAdvisor reviews and ratings, and at the top of the list sits a Chicago institution: Portillo's.

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Opened as a small hot dog stand in 1963 in Villa Park, Illinois, the fast-casual chain has grown to 58 locations, expanding its just-hot-dogs menu to one that serves ribs, pastas, sandwiches, soups, salads, and more. Of course, Portillo's still serves lots of hot dogs, too, in the traditional Chicago style—their "everything" jumbo hot dog includes mustard, relish, celery salt, chopped onions, tomatoes, pickle, and peppers on a steamed poppy seed bun.

But there's one location of the chain that reigns supreme: the Portillo's in Chicago’s River North neighborhood (100 W. Ontario St.) was deemed the overall winner for quality and service.

In addition to the fast-casual category, TripAdvisor published lists for the best fine-dining restaurants in the world (Au Crocodile
in Strasbourg, France was named number one) and the best "every day dining" restaurants (Pane & Vino in Miami Beach, Florida was first.)

As you likely know, people have strong feelings about Portillo's, which is known for its cult Midwestern following. Last year, in response to the restaurant's discontinuation of its lemon cake, one man posted a "$300 bounty" on the dessert to Reddit. The post gained so much traction that Portillo's eventually added it back on the menu for a limited time.

Following Portillo's in the fast-casual category was Earl of Sandwich (Las Vegas, NV), Shake Shack (New York, NY), and Blaze Pizza (Orlando, FL), respectively.