To make sourdough starter, all you need is equal measures of flour and water. Stir it every day for a few days. At some point, usually after two to four days, the starter will be ready for feeding.

For more detailed instructions, see Make Your Own Sourdough Starter at Home.

When Do I Start “Feeding” My Starter?

• When you see tiny bubbles throughout the batter, it’s time to start feeding. You may have to enlarge this picture to see the bubbles. When you see plenty of bubbles throughout the batter, even after you stir it, discard about half of your starter. Add a cup each of flour and water. Do this every day until the starter is ripe.