Orange Sherbert?

I was hanging out with a group of friends the other day, and for some reason we all started talking about watermelon Sherbert and orange Sherbert, and a girl from the UK who was with us looked at us like we were effing crazy and asked us if we were kidding.

She told us that it's "Sherbet" not "Sherbert," and we didn't believe her, so we looked it up and apparently it's always been "Sherbet."

Does anyone else remember there being a second R is the word "Sherbet?"