Which classic fairy tale was NOT written by the Brothers Grimm?

If you haven’t read any of the Brothers Grimm's original fairy tales, you’re in for a bad time. Kids must have been built different back then because these aren’t whimsical tales about friendship and love, but straight-up horror. We’re talking brutal body-horror levels of disturbing here.

I don’t know what Disney was smoking to think turning those original stories into kids’ movies was a good idea, but I guess that’s why I’m writing trivia questions and not a frozen head beneath Disney World. It would be like trying to make Friday the 13th or A Nightmare on Elm Street into family comedies.

Most classic fairy tales were collected, retold, and/or written by the Brothers Grimm, but they weren’t so creative as to publish all of them. There is one well-known fairy tale that has an original story just as dark and disturbing as the others but comes from a different author. Which one is it?