Gluten-free sourdough bread is not as sour as traditional sourdough bread. However, a little sour may be all you need. This bread has a soft crust but toasts up nicely. The texture is similar to its gluten counterpart, which is often difficult to achieve in a gluten-free recipe. However, it is a little heartier. To most, its texture is worth the additional weight.
Sourdough bread is an advanced recipe, even for gluten bakers. However, many newbies successfully make this sourdough bread, and so can you.
1 egg, beaten, at room temperature, for basting (or cream, for egg-free)
Oil a French bread pan*; set it aside. (Alternatively, to a large roasting pan, line-up several large, heat-proof, glass jars (canning jars without lids work perfectly) down the middle of the longest portion, lying them on their sides. (Ideally, the jars should be as tall as the sides of your roasting pan, but a little higher won’t hurt.) You want to create a wall down the center of the pan which will form a divider. Lay a sheet of parchment over the jars, leaving plenty of overhang on the left and right sides of the pan, creating two hammock-like cradles between them. Push the paper down on the left and right sides of the jars to form the two hammocks/pockets where the dough will lay.) You can either lay the roasting pan on a baking sheet and tuck the parchment paper underneath the roasting pan or attach to the pan using binder clips. (Thank you to Kendra, recipe tester, for the photo.)
Whisk together the potato starch, cornstarch, tapioca flour, xanthan gum, baking powder, baking soda, sugar, salt, and yeast in a separate bowl.
Add the sourdough starter, oil, buttermilk, and warm water to the bowl of your stand mixer. Mix on low speed until blended, 15 seconds.
Combine the dry mixture into the wet mixture, and beat on low speed, using the whisk attachment, until moist. Increase the speed to high and beat for about 4 minutes. (You want to create a mixture that is thicker than cake batter but not as thick as cookie or gluten bread dough. This dough is a bit softer/thinner than most of my bread recipes.)
While the dough is mixing, set aside a gallon-size resealable storage bag and a pair of kitchen/clean scissors.
Using a large serving spoon, scoop the mixture into one of the bottom corners of the bag. Cut 2-inches off of the same corner.
Beginning about 3 - 4 inches away from the edge of the pan, squeeze half the dough on one side of the pan and the other half of the dough on the other side. Set aside to rise in a warm environment for 30 minutes or until it reaches the top of the pan or doubles in size. (Too many holes forming on top of the dough is an indication of over-rising, which can result in baked bread that smells and tastes like yeast.)
Midway through the rising process, preheat the oven to 400°F. Place a rimmed baking sheet in the lower portion of your oven and fill with 2 cups of water. Using a sharp knife dipped in water, slice 4 or 5 slits in the top of the dough, at an angle, about 1/4-inch deep.
Baste the tops of the loaves with beaten egg and bake for 15 minutes.
Baste again with egg wash and bake for an additional 20 minutes.
Remove the bread from the oven and immediately transfer to a wire rack to cool. Slice as desired. Use this bread for sandwiches, garlic bread, or cut them into cubes and serve with spinach dip. You can even enjoy with just butter. See the below hoagie photo that one of my recipe testers made with his sourdough bread:
Freeze slices of leftover bread in a resealable storage bag. Toast or microwave on low to reheat.
*If using a perforated French bread pan, instead of oiling the pan, line it with parchment paper.
If your oven is large, and the bread does not brown enough, set the oven to high broil for about 1-1/2 to 2 minutes to darken the crust.
While this loaf is not as high as traditional sourdough bread, you can achieve a higher rise by substituting half of the potato and cornstarch with tapioca flour. However, it creates a chewier and less gluten-like texture.
If your bread doesn’t turn out as sour as you would have hoped, instead of pouring off some of the starter liquid, stir it in. In addition, the more liquid in the dough, the higher the rise. However, too much liquid can cause bread to fall. The more liquid in the dough, the longer it needs to bake. With some practice, you’ll be a pro in no time.