matt groenings favorite episode

More than most other shows, it's almost impossible to pick a favorite episode from The Simpsons. When a show is around for 20 years, it's hard to narrow it down to the one episode that stands out among all the rest. Sure, there are episodes that stand out to me immediately (none from the past four or five years, that's for sure), but it would be hard to choose my favorite.

The new issue of Emmy magazine asks several writers and producers from the show what their favorite episodes are, including creator Matt Groening. Can you guess which episode he picked?