Here’s a recipe, or as close as possible since I was free-styling it that morning.
The night before, take out of the fridge your sourdough starter (see my feature “Taming the Wild Yeast“). Transfer to a clean bowl and mix in the hootch (dark liquid on top) if you like more assertive sourdough flavors; pour off the hootch if you don’t. You’ll need about 1 cup of starter. Stir in about 2 cups of unbleached AP flour and 1 cup tepid, filtered water. Covered with a cloth and let ferment overnight.