Is there a candy bar named Sir?

There is no widely known candy bar named "Sir". It's possible a local or limited-edition candy bar might exist with that name, but it's not a major brand.

It's likely you're thinking of a similar-sounding name. Perhaps you're thinking of:

* Snickers: A popular chocolate bar with peanuts, caramel, and nougat.

* Mr. Goodbar: A chocolate bar with peanuts.

* Sir Galahad: A fictional knight from Arthurian legend.

Let me know if you have any more clues about the candy bar you're thinking of!