Basic Sourdough Starter

1. Mix 1 cup whole-wheat flour and 1/2 cup water in a nonreactive container, such as a glass or stainless-steel bowl, until thoroughly combined. Cover loosely with a lid or plastic wrap and let sit at a warm room temperature (ideally around 70 degrees F) for 24 hours.

2. Using your kitchen scale, measure 4 ounces starter (about 1/2 cup) into a second nonreactive container; discard the rest of the starter and wash the first container to use tomorrow. Weigh 4 ounces all-purpose flour and add it along with 1/2 cup water to the reserved starter. Stir thoroughly and loosely cover. Let rest about 24 hours.

3. As in Step 2, weigh out 4 ounces starter into a clean nonreactive container and discard the rest. Add 4 ounces all-purpose flour and 1/2 cup water, stir thoroughly and loosely cover. Let rest at room temperature for 12 hours. You'll now start feeding the starter approximately twice a day.

4. Repeat Step 3 for the next 2 days, feeding the starter approximately twice a day (4 feedings total). On the sixth day, or after about 8 feedings, the starter should be doubled in volume, bubbly and have a mild, vinegary aroma similar to cider vinegar. If not, repeat Step 3 for 1 to 2 more days (2 to 4 more feedings).

5. When the starter is risen, bubbly and smells mildly vinegary, feed again with 4 ounces flour and 1/2 cup water, stirring thoroughly and covering loosely. Let rest 6 hours, or up to 12 hours at most.

6. Measure 4 ounces of the starter into a nonreactive container, such as a 1.5-quart crock or jar, that it can be kept in permanently. (Discard the rest.) Feed with 4 ounces all-purpose flour and 1/2 cup water, stirring thoroughly and covering loosely. Let rest at room temperature for 3 to 6 hours before covering tightly and storing in the refrigerator.

7. At least once a week, feed the sourdough to keep it active, adding 4 ounces flour and 1/2 cup water and stirring thoroughly. Remove starter as needed; if the container gets too full to continue feeding, discard excess starter or use it in a recipe. Always keep at least 4 ounces starter in the container.

Tips

To make ahead: An established starter, fed weekly, will keep in the refrigerator indefinitely.

Equipment: Kitchen scale, 1.5-quart crock or jar

Tips: Sourdough starters develop more quickly in warmer environments (say, an 85 degrees F summer day) and more slowly in colder ones (a drafty 65 degrees F kitchen come wintertime). The starter may take more or less time depending on your surroundings, so watch for the cues and use the timing given in the recipe as overall guidelines.

If you see an 1/8-inch to 1/4-inch layer of what looks (and smells) like vinegar on top of your starter, it means your sourdough is underfed; feed it twice that day, at the usual 12-hour intervals, to bring it back to form. If the sourdough fully separates (i.e., a 1-inch layer of vinegar is floating on top of a thin, dormant starter), discard and start again.

The sourdough should remain fragrant and slightly bubbly in the fridge. Feed once each time before using to get the starter nice and active.