In a glass bowl or measuring cup, combine all the ingredients. Cover loosely with plastic wrap and store at room temperature.
Every 12 hours, discard all but 4 ounces and feed by stirring in 1 cup (4 ounces) of unbleached all-purpose flour and ½ cup (4 ounces) of water. Cover loosely with plastic wrap and store at room temperature.
The starter is ready to be used when about 1 teaspoon of starter floats in a glass of water (after 2-3 feedings). If it doesn’t float, continue with 1-2 feedings.
Notes
If starter will not be used within 24 hours, maintain by storing covered in the refrigerator and feeding once a week (don’t forget to discard!). To revive, feed 2-3 times prior to using.