These muffins are a Nancy Silverton recipe, by way of David Lebovitz's blog. He says that they are "...quite different than other muffins. For one thing, they're much, much lighter in texture. And for another, they're not very sweet." He's right. [of course he's right! he's David Lebovitz!]
Based on Jess's suggestion, I upped the orange zest. I was just about to say that I think these'd be great with marmalade, but then who am I kidding? I think almost everything would be great with marmalade.
Nancy Silverton's Bran Muffins