I've been asked how I get the big holes, and how I fold. Whether you are working with a bread dough that uses commercial yeast, or with sourdough, the same principles seem to apply from what I've experienced. Obviously, there are others here more experienced in sourdough who may have different techniques. It depends on what works for you.
What gives me the big holes is to use a very wet, soft dough, fold it 2-3 times for the first 60-90 minutes of fermenting to strengthen the gluten, and when you're ready to shape, VERY GENTLY pour it out onto your counter, VERY GENTLY fold the sides into the center to gather it up into a boule without degassing it in the least, flip upside down in your hand and tighten it into a boule by pinching the seam underneath closed. Then place it smooth-side down (seam-side up) into a floured banneton or proofing basket. Do not skimp on the rising time - if it needs 5 or 6 hours rather than the 3 stated in the recipe, let it rise all the way, and make sure your starter is very active.
I really like this bread, I just made it again this past weekend and it came out equally well as it did in the photo at top. It had more of a sour bite to it this time from the wet rye starter.
Thom Leonard’s Country French Bread (from "Artisan Baking" by Maggie Glezer)
Makes one 4 lb. (1.8 kilo) loaf
Time: about 18 hrs. with 30 minutes of active work
The evening before baking make the Levain as follows:
45 g ( 1 oz) fermented rye sourdough starter refreshed 8-12 hrs before (I use a batter-like starter made with equal weights water to rye flour, not a firm starter. If you only have a white flour starter, use that and just substitute 30 g of the white flour in the final dough with rye flour)
120 g (3.3 oz) lukewarm water
140 g (5.3 oz) unbleached all-purpose or bread flour (see my note below on flour)
Dissolve starter in the water in a small bowl, then add flour and beat this batter-like dough until very smooth. Place in covered container and ferment at room temp (@70F) until doubled, 8-12 hrs.
NOTE: I use only King Arthur All-Purpose flour rather than bread flour as it has a high enough protein content and a high ash content compared to other all-purpose flour. The high amount of protein found in most “bread flours” makes the crumb too tough for my taste.
Next day make the final dough as follows:
100 g (3.5 oz) Whole Wheat Flour (if you like your bread a little darker add up to 350 g whole wheat here and use 250 g less white flour below)
1030 g (36 oz) unbleached all-purpose flour (King Arthur has best protein and ash content. If using a white flour starter in the levain rather than rye, substitute 30 g of the white flour here with 30 g rye flour)
660 g (24 oz) warm water
all the fermented levain you made the night before (305 g or 10.6 oz)
23 g (0.8 oz) sea salt (preferably grey Celtic sea salt if you can find it, often sold in health food stores)
Mix By hand: combine all flours in large bowl. Add the warm water to the fermented levain to loosen it from container. Pour the watered levain into the flours and mix with spoon, dough whisk, or hands until just combined. Cover with plastic wrap and let rest (autolyse) for 20-30 minutes. Turn dough out onto work surface, knead for 10 minutes, then add salt, and knead for another 5 minutes until salt has dissolved and dough is very smooth and shiny.
Mix By stand mixer: same as by hand except leave in mixer bowl after autolyse, then mix with dough hook on lowest speed for 5 minutes. Add salt and knead in mixer at low speed for another 4-5 minutes until very smooth and almost cleans the bottom of the mixing bowl.
The dough should feel soft, sticky, and extensible at end of kneading. If it is too stiff and dry, add a few more drops of water until dough just barely clears bottom of mixing bowl at end of kneading if using a stand mixer, or until dough feels soft and stretchy, and slightly sticky, if hand kneading. Softer, wetter doughs give you larger air holes in the baked loaf, which also gives the bread more flavor.
Fermenting: Place dough in lightly-oiled bowl at least 3 times its size and cover with plastic wrap. Let ferment for 3 hours at room temp (@70F) until well-expanded but not yet doubled in bulk. Turn dough 3 times at 30 minute intervals by gently folding like a business letter and flipping upside-down, (that is, turn once at 30, 60, and 90 minutes into fermenting time), then leave the dough undisturbed for remainder of time. OR: for even more flavor, ferment at room temperature for one hour (turning 2 times, once at after 30 and once after 60 minutes), then retard overnight in fridge, warming up again next day at room temp. for 2-3 hours before shaping.
Rounding and resting: Turn dough out onto floured work surface, and very gently round it into a tight boule. Cover with plastic and let rest for 10-15 min. to relax the gluten. While resting, prepare your basket or banneton by dusting with flour. If you’d rather make 2 smaller boules than one large one, divide the dough in half with a dough cutter, and gently form each piece into a tight boule.
Shaping and proofing: Shape the dough into an even and tight round loaf (or leaves if making 2 smaller boules) without deflating it. Place dough topside down into the floured basket or banneton. Lightly sprinkle the top of the dough with flour, cover with plastic wrap and proof for 4 to 4.5 hours at room temperature (@70F) until at least doubled in volume and a slight dent remains when pressed with finger.
Preheating oven: At least 45 minutes before dough is fully-proofed, preheat oven with baking stone on middle rack to 500F.
Bake: Gently flip the dough upside down to release it from the banneton/basket onto semolina-dusted parchment on an over-turned baking sheet or wooden peel, or directly onto a semolina-dusted peel if not using parchment. Slash the boule with a razor in a pound sign (#) design, or in a spiral, cross, or any other desired pattern, as long as the slashes go completely across the top to allow for even expansion during baking. Slide parchment onto hot baking stone in oven, or onto semolina dusted baking stone if not using parchment, and quickly mist side walls of oven with water in a mister (do not spray near the oven light!) and quickly shut the oven door to prevent heat and steam from escaping. The steam helps the dough rise very quickly in the hot oven (called “oven spring”) and also makes the crust more brown and crisp. Turn oven down from 500F to 400F and set oven timer for 30 minutes (20 minutes if making 2 smaller boules). Continue misting every 30 seconds just 3 or 4 times for first 2 or 3 minutes of baking, then leave to bake. When first 30 minutes are up, open oven and rotate loaves around to even out browning. Set timer for another 30 minutes (20 minutes for 2 smaller boules) and check the loaf when that time is up. If it is still a light color brown, leave in for another 5-10 minutes until it is a deeper brown but not burnt, then probe center of loaf with instant-read thermometer, loaves are done when thermometer reads at least 205F in center. If they are getting burnt but center is not done, your oven is too hot, turn it down another 25 degrees or so next time. Let cool thoroughly on rack before cutting as the centers are still cooking, at least 2 hours.