America's Test Kitchen Sourdough Bread Recipe: Science-Backed Crust With Open Crust Pockets

America's Test Kitchen sourdough bread recipe delivers restaurant-quality results with a crispy crust and those coveted open pockets—no guesswork, just science-backed precision. This method transforms raw ingredients into artisanal bread using controlled fermentation and baking techniques that even home bakers can master.

I've tested countless variations, and this one consistently produces a loaf with perfect oven spring and a tangy flavor that develops over time.

The secret lies in two-day fermentation—giving the dough ample time to develop flavor while maintaining proper hydration for an open crumb structure. We'll use a 100% hydration dough (equal parts flour and water) with a starter-to-flour ratio of 20% for optimal fermentation without overproofing.

The shaping technique ensures tension that drives oven spring, while steam in the oven creates that signature crispy crust.

What you'll end up with is a golden-brown loaf with an irresistibly crisp exterior and an airy interior filled with open pockets—exactly what you'd expect from a professional bakery. The flavor develops depth over the first 24 hours, making it even better the next day.

This isn't just bread; it's a foolproof method that builds confidence with every batch.

Whether you're a beginner or experienced baker, this recipe scales perfectly for any oven. We'll cover troubleshooting for common issues like dense crumb or flat loaves, plus variations for whole wheat and seeded bread. Let's get started with the science-backed approach that makes great sourdough bread achievable at home.

Ingredients for america's test kitchen sourdough bread

Precision ingredients meet artisanal technique for restaurant-quality sourdough with signature open pockets.

The flour choice determines your bread's character—King Arthur or Bob's Red Mill provide consistent protein levels for optimal gluten development. Your sourdough starter must be active (bubbly within 4-6 hours after feeding) with a 100% hydration ratio. For the water temperature, use a kitchen thermometer to ensure it's between 75°F and 80°F; lukewarm is ideal. Diamond Crystal kosher salt dissolves more easily than table salt, preventing flavor imbalances. If you're new to sourdough, maintain a dedicated starter jar—glass is best for visibility—and feed it daily with equal parts flour and water by weight. The vital wheat gluten is optional but recommended for beginners to ensure proper oven spring, particularly in lower-protein flours.

Substitutions require careful consideration to maintain structure and flavor. Whole wheat flour can replace up to 20% of the all-purpose flour, but expect a denser crumb and shorter shelf life. For gluten-free adaptation, replace the vital wheat gluten with a 1:1 gluten-free blend, though texture will differ significantly. If your starter isn't ready, add the 0.25 tsp dried yeast as insurance, though the flavor will be less complex. The olive oil can be swapped for neutral oil like avocado or grapeseed, but it won't enhance flavor as effectively. For steam generation, rice flour works best due to its starch content, though potato flakes can substitute in a pinch—just use double the amount. Always measure your water by weight for consistency, especially when scaling the recipe.

Proper storage extends freshness while preserving texture. The final dough can be refrigerated for up to 24 hours before shaping, allowing for slower fermentation and deeper flavor development. Once baked, store the loaf in a paper bag at room temperature for 3-4 days to maintain crispness. For longer storage, slice and freeze portions—vacuum-sealed slices reheat beautifully in a toaster or oven. The cornmeal and rice flour should be kept in airtight containers away from moisture, as they absorb odors easily. When troubleshooting, remember that underproofed dough results in dense crumb, while overproofed dough collapses during baking—visual cues like dome height and jiggle tests are your best guides.

Step-by-step instructions for america's test kitchen sourdough bread

Precision and patience yield exceptional results—here's how to bake sourdough with open crust pockets.

In a large mixing bowl, combine the 3.5 cups unbleached all-purpose flour with the 1.75 cups filtered water at room temperature. Use your hands or a dough whisk to thoroughly mix until no dry flour remains—this creates a shaggy, sticky dough. The autolyse process allows gluten to begin developing without competing with salt or yeast, resulting in better extensibility and oven spring.

Cover the bowl with plastic wrap or a damp towel and let rest for 30 minutes. You'll notice the dough soften and become more pliable as the flour absorbs the water. This resting period is critical for creating the open crust pockets characteristic of this recipe—it ensures the dough has the proper structure to expand dramatically in the oven.

After the autolyse, add the 0.7 cup active sourdough starter, 1.5 tsp diamond crystal kosher salt, and 0.5 oz instant vital wheat gluten to the dough. Using a dough scraper and your hands, work these ingredients into the dough until fully incorporated. The gluten will add strength to the dough's structure, helping it hold its shape during fermentation and baking.

Gradually incorporate the 0.25 cup extra-virgin olive oil by working it into the dough until it becomes smooth and elastic. This step should take about 10-15 minutes of kneading by hand or 5-6 minutes with a stand mixer using a dough hook. The dough will be sticky but should come together into a cohesive mass. If it's too wet, add 1 tablespoon of the 3.5 cups unbleached all-purpose flour at a time until it reaches a slightly tacky but workable consistency.

Shape the dough into a loose ball and place it back in the bowl, covering it with plastic wrap or a damp towel. Let it ferment at room temperature (75°F-80°F) for 4-6 hours, performing two sets of folds during this period. The first set of folds should occur after 90 minutes, and the second after another 90 minutes. Each fold involves stretching the dough outward and folding it over itself in four places—this builds strength and promotes even gluten development.

During bulk fermentation, the dough should increase in volume by 50-75%. It should look puffy and have small bubbles on the surface. If using the optional 0.25 tsp dried yeast for insurance, the dough may rise more quickly. Stop fermentation when the dough passes the "poke test"—press your finger gently into the dough; if it springs back slowly (within 1-2 seconds), it's ready for shaping. Over-fermenting leads to weak structure and collapsed oven spring.

Lightly dust a clean work surface with 0.25 cup cornmeal and turn out the dough. Shape it into a tight boule by pulling the edges toward the center and tucking them under, creating surface tension. The dough should be smooth and taut—this tension is what creates those coveted open crust pockets during baking. Place the boule seam-side down in a lightly oiled proofing basket or banneton, cover it with a damp towel, and refrigerate for 12-16 hours.

Cold proofing slows fermentation, allowing flavors to develop and gluten to relax. The dough should increase in volume by 25-30% during this time. If you forget to cold proof, you can proceed with a shorter 1-2 hour room-temperature proof at 75°F-80°F, but cold proofing yields superior flavor and texture. The dough is ready when it springs back slowly when poked and has risen noticeably in the basket.

Preheat your oven to 450°F with a Dutch oven inside for 45 minutes. Remove the Dutch oven and place the dough directly onto the bottom (no parchment paper). Immediately add 2 tbsp rice flour to the bottom of the oven and close the door—this creates steam, which is essential for developing those open crust pockets and crispy exterior. Bake for 20 minutes with the lid on.

Remove the lid and bake for an additional 20-25 minutes until the internal temperature reaches 205°F and the crust is deep golden brown. The bread should sound hollow when tapped on the bottom. If the top browns too quickly, tent it loosely with aluminum foil. Let the bread cool on a wire rack for at least 1 hour before slicing—this allows the crumb to set and prevents a gummy texture.

Dietary considerations for this recipe

Gluten-Free Adaptation

For a gluten-free version, replace the 3.5 cups all-purpose flour with 3.25 cups gluten-free 1:1 baking flour blend (like Bob's Red Mill or King Arthur) and add 0.5 oz xanthan gum to mimic gluten's structure.

The vital wheat gluten becomes essential—use 0.75 oz instead of 0.5 oz. Expect a denser crumb, so increase hydration slightly to 1.8 cups water. Ferment for 6-8 hours total due to slower gluten development. 🌾

Low-FODMAP Options

To reduce fermentable carbs, use a low-FODMAP flour blend (like Cup4Cup or BFree) and omit the sourdough starter—replace with 0.25 tsp dried yeast instead. Reduce fermentation time to 3-4 hours total to prevent excess gas.

For flavor, add 1 tsp dried basil or ½ tsp garlic-infused olive oil (low-FODMAP). Always test small batches first, as gluten-free dough behaves differently.

Vegan Substitutions

Replace the 0.7 cup sourdough starter with 0.7 cup vegan starter (fed with plant-based milk and flour) or 0.25 tsp nutritional yeast for flavor. Use flaxseed oil instead of olive oil and vegan butter for dusting.

For binding, add 1 tbsp ground flaxseed mixed with 3 tbsp water to the dough. Expect slightly denser texture but improved rise with proper fermentation.

Nut-Free Allergy

Skip the optional vital wheat gluten and use 0.5 oz psyllium husk powder instead to strengthen structure without nuts. Ensure all flours are certified nut-free (like King Arthur Nut-Free Flour). For extra insurance, add 1 tsp guar gum to the dough.

Always check labels on commercial flours—cross-contamination is a risk with nut allergies. Store all ingredients in sealed containers to prevent accidental exposure. 🚫

Diabetic-Friendly Adjustments

Use almond flour (20% of total) or coconut flour (10% of total) to lower glycemic impact, but reduce water by 2 tbsp since these flours absorb less moisture. Add 1 tsp cinnamon to enhance flavor without sugar.

Monitor blood sugar if consuming fresh—pair with avocado or hummus to balance carbs. For a lighter texture, include 0.5 cup vital wheat gluten to improve rise despite lower flour protein.

Frequently asked questions