Differences between the chains include the secret sauce they put on Big Boy double deckers. ExploreFrisch’s closings list: The ones that have closed, may close, or are staying open The Michigan ...

It's no secret that, for the most part ... California-based Big Boy uses a Thousand Island-ish "Big Boy" sauce on its burgers; Shake Shack's Shack Sauce is made with mayo, ketchup, dill pickles ...