If you are like me, you never heard of sourdough discard and perhaps have never experimented with making sourdough bread, so let me explain. When you first make the starter, you simply combine unbleached flour and filtered water in equal parts. You add the same amount every twelve hours for seven days leaving the mixture covered with a napkin or towel in a warm place. (I put it in the oven with the light on.) Each time you add the flour and water, you mix vigorously to add air. The starter picks up natural yeast from the air and ferments. On day seven your starter should be bubbly, doubled in bulk, with a sour smell. You "discard" all but half a cup and continue adding more flour and water once a day.
