(FYI to those who might wonder, challah = braided egg bread, akin to brioche, that's a staple of the traditional Jewish sabbath meal every Friday night.)
I think I know the answer to my own question (Fishman's Kosher), but perhaps I'm missing an even better loaf of challah from some other bakery here in the Twin Cities.
I consider the "egg braid" at Rustica is a close second to Fishman's. (they don't call it challah as it's not actually kosher)
The challah from Breadsmith and Yum are both edible but not even close to the wonderful loaf that Fishman's produces.
What say ye?