I love finding ways to have either my characters or my narrator relate backstory so that it sounds completely natural, organic, and necessary.
I love it when a writer is able to have his characters bring up back story because it’s needed, because they need to be talking about it with one another.
A really excellent writer like Stephen King is able to do so in such a way that it keeps you interested — because he keeps dropping little bits of information that make you want to know more.
Sometimes unraveling the backstory is as much fun as finding out what happens next in the main story.
The Stand is an excellent example of that. Not that I’m trying to suggest that you have to write a tour de force epic in order to do good back story!