Since meeting Uri Scheft a few times on his visits to New York, I'm always was curious to check formulas he's posted on his Lehamim Bakery Facebook. When a challah recipe appeared I jumped to it and adapted it to a sourdough. Toying with using orange flower water and raisins, I ultimately opted to just go standard challah at this first try.
With a whopping sixty-four percent of sourdough overall to compensate for yeast in the straight formula, I was really pleased at the fermentation being so quick. Maybe a levain left in the fridge for three weeks is just as strong as one refreshed?