Feed your starter anywhere between 4-12 hours before starting this recipe.
Measure out your 525 grams of filtered, room temperature water into your large bowl and add 100-125 grams starter.
Add your 700 grams of flour and mix, scraping the sides of the bowl as you go, until you have a shaggy dough.
Cover with your bowl with a shower cap or bowl cover for 30 minutes to allow for autolyse (this makes sure the flour fully absorbs the water).
Measure out your 14 grams of sea salt (I just tare the scale and use my bowl) and sprinkle onto your dough evenly. Wet your fingers to pinch the salt into the dough.
Wet your hands again and do your first set of coil folds (stretch and folds work here, too). Cover and let sit for another 30 minutes.
Wet your hands and do another set of coil folds. Cover and let sit for 30 minutes.
Do one more set of coil folds and cover. Now is time for bulk fermentation! This is where your dough ferments and breaks down gluten to form something that is easy to digest and is gut healthy.
Cover and let sit in a warm place overnight or for for 8-12 hours. I recommend placing on top of your fridge, but some people have success with putting inside the oven with the oven light on - just don’t forget it’s there!
Once your dough has around doubled in size the next morning, gently tug at the sides of your bowl and lay your dough out on a lightly floured surface.
Stretch your dough into a large rectangle. Use your bench scraper to cut the dough in half. Now its time to shape.
Choose a half to work with. Remember that high hydration sourdough likes to be handled gently. Pull the bottom side of your dough up toward the middle and lay there. Then, take either sides of the dough and wrap them toward each other, sort of like your swaddling a baby. Then, take the top of the dough and pull out gently and then back to the center. You'll do this and then quickly roll your dough over to reveal the smooth backside. When you have it all rolled up, move it around on the counter in round motions to gently build tension while you push and pull it toward you.
Do the same to the other half of your dough. Now, let your dough rest for 20 minutes.
Gently pull again to build tension in both loaves, this time for not as long. You want your dough to have a smooth surface. If you overwork your dough (and this is why it's important to be gentle), your seams will rip and you'll risk having a flat, lifeless dough that doesn't hold its shape. Better to underwork it than overwork it.
Prepare your banneton baskets by generously flouring them with whatever flour takes your fancy.
Use your bench scraper to gently transfer your shaped loaves into your banneton baskets, seam side up.
Cover with your shower caps or bowl covers and I like to use a grocery store bag or produce bag to put my loaves inside. The goal is to seal in moisture and keep air out.
Place inside fridge and let sit anywhere from 2-12 hours. When you're ready to bake, perform the poke test: poke dough with floured finger. If dough springs back slowly about halfway, it's ready to bake! If dough springs back right away, it is underproofed and needs to sit longer. If it doesn't spring back at all, it is overproofed.
When ready to bake, preheat your cast iron dutch oven at 500 degrees F with the lid on. I like to have two dutch ovens on hand so that I can bake two loaves at a time, thus saving on time and electricity. If you only have one, just bake one at a time.
While your oven is preheating, take one of your loaves out of the fridge and transfer to a sheet of parchment paper.
Now is the fun part: scoring! Use your flour of choice to smooth over the face of your dough. Take your scoring blade and bring out your creative side while you etch whatever patterns you'd like. It is important to score an "ear" to your dough either down the side or you can do a simple cut down the middle. See the FAQ's down at the bottom of this post for more information on that.
When your oven is preheated, take the lid off and place 2-3 ice cubes on the bottom of your dutch oven. Try to place them evenly but don't overthink it.
Use the sides of your parchment paper to transfer the loaf gently into the dutch oven and place the lid on top, making sure its on there firmly. Bake for 20 minutes.
After the 20 minutes is up, reduce the temperature to 475 degrees F and take the lid off your dutch oven. Bake for another 20 minutes.
Once your bread is done, don't slice into it yet! I know it's tempting and I've broken the rules before, too. You'll thank yourself if you wait at least 30 minutes. Let cool on a cooling rack and use a bread knife to slice.