I don't know about a secret menu, but I know certain areas have different menu options. The Green Chilie Double is localized in Arizona. Went to one in Texas and and they don't have it. I believe they had a special BBQ burger.
Yes, they do. Amazingly, I found it on Google. Not sure why you wouldn't have looked there first... https://www.wideopeneats.com/the-top-whataburger-secret-menu-items/
Secret , like hidden or like for special people ?
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