How to Make a Healthy, Bubbly Sourdough Starter in a Jiff

With the artisanal bread movement taking off around the country, sourdough has seen a well-deserved spike in popularity. It's easy enough to make this bread at home (and sourdough bagels, pizzas, get the drift). Every recipe begins with a sourdough starter. Our method uses a smart hack to get the starter ready super quick.

By Kelsey Mueller, Senior Digital Editor and James Schend, Food Editor

A loaf of sourdough bread on a cutting board with slices resting next to it.

Sourdough bread is leavened (or raised) with natural yeast, which is found on your kitchen surfaces, wooden spoons and even your hands and the air around you. When building a sourdough starter, you're capturing those yeasts and using them to not only leaven dough but also to enhance the flavor of bread.

The catch is, building a traditional starter that's strong enough to make airy leavened breads can take weeks or even months. Our Test Kitchen has a nifty hack to jump-start the process: just add some commercial dry yeast at the beginning. Read on to learn how to make a starter that's ready for baking in days.

Test Kitchen Tip: With proper care, your sourdough starter can live indefinitely. Some bakers claim to use starter that's decades old. One US woman won a Wyoming State Historical Society award for her 122-year-old starter!

How to Make a Foolproof Sourdough Starter

You'll need:

  • 2 cups all-purpose flour, or other flour of your choice (whole wheat, a blend of white and wheat, ancient grains like kamut, etc.)
  • 1 package (1/4 ounce) active dry yeast
  • 2 cups warm water (110° to 115°)

yeast, flour and water mixture sitting in a large glass bowl with a cloth overtop it and the discarded yeast packet and sugar jar beside it

Step 1: Mix

Grab a large (4 quart or so) container you won't mind dedicating to your starter for a week or more. Use glass, ceramic or plastic, not metal.

Combine the flour and yeast in the container. Gradually, stir in warm water until smooth.

Cover loosely with a kitchen towel or a piece of cheesecloth.

yeast mixture sits in a large glass bowl with bubbles peeking though its surface

Step 2: Wait

Let your mixture stand in a warm place until it gets bubbly, usually two to four days. In cold weather, it can take up to a week. Stir your starter daily with a wooden spoon or clean hands to encourage activity.

When the starter is ready, it will be bubbly, smell sour, and have a cap of clear liquid floating on the top.

Test Kitchen Tip: How can you tell if your starter has gone bad? Good starter will darken a bit and have a strong smell. If it has mold, a deeply offensive or rotten odor, or turns a different color entirely, it has gone bad. Toss it!

Step 3: Feed Your Starter

Pour off the liquid on the top—or stir it in if you'd like extra sour flavor. Discard half of the starter. For each 1/2 cup of starter you keep, add 1/2 cup flour and 1/2 cup warm water. Stir until smooth. Cover loosely and let stand in a warm place until bubbly.

Why throw away starter? While discarding half of the starter seems like a waste, you’re actually helping it to thrive and taste better. Trust us, don’t be tempted to keep it all, otherwise you’ll end up with gallons of very hungry starter. Also, by eliminating half of it, the starter that’s left is happier because it’s not competing with other yeast cells for food. Lastly, from a chemical standpoint, removing excess starter helps keep the ph level at the sweet spot where the yeast loves to live.

What if my starter rises and then sinks before I get a chance to bake? Don't worry. This just means that you missed the prime time for baking. Simply stir the starter, add a dash more flour and water, and wait for it to rise again.

Test Kitchen Tip: You can control the timing of your starter. If you'd like it to rise quickly, warm it up. Use slightly warmer water in your mix and let it sit in a warm place. If you want to let the starter rise slowly, use cooler water or let sit in a cooler place, like a basement. Note that the longer your starter takes to rise, the more tang it will have.

starter mixture in a glass bowl held up with one hand showing what clings to the bowl after the mixture is drained

Step 4: Bake

When bubbly and roughly doubled in size, your starter is ready to use! Pour off the amount needed in the recipe. (Save the rest!)

Check out our recipe for foolproof sourdough bread.

You can also stir a cup or two of starter into most breads and pizzas—even stuffed crescent rolls!

Step 5: Saving Your Starter

The remaining starter will survive in the fridge for up to two weeks before it needs another feeding. Simply cover the starter container and stick it in the fridge.

When you want to use it again, bring the starter to room temperature for an hour or two, and then feed the starter (No. 3 above). Wait for it to bubble, and then use it. You can repeat steps three and four as often as you like. With regular feedings, your starter will continue to get stronger, with more leavening power in your breads.

Test Kitchen Tip: Can I make a starter without adding yeast? We like to use commercial yeast to kick-start the process, but you can also use only flour and water. Expect it to take longer to bubble (closer to one week and up to two). Once it bubbles, you'll want to feed the starter twice a day for two or three days. This will build up the natural yeasts in the mix and make your starter strong enough to leaven bread. Once the starter develops a regular pattern of bubbling, rising, and sinking, it's ready to use.