MICROBIOLOGY
Sourdough bread is made by a mixture of wild yeast and lactic acid bacteria. In my case, we started a culture from cottage water and whole wheat flour in the Muskoka area of Ontario (April 2020). The yeast add gas/alcohol/flavour as they ferment and the lactic acid bacteria drop the pH with lactic acid while fermenting sugars to offer the sour flavour and bouquet.
Below is the long but forgiving protocol that I follow - it’s intimidating but becomes routine with repetition. There are shorter protocols out there (e.g., nice simple one on pgs 44-45 of this real estate magazine issue: https://issuu.com/goodcomagazine/docs/issue_131_flipbook) if you are looking for fewer steps.
LINKS
How I made the starter originally (from filtered Muskoka lake drinking water): https://www.theclevercarrot.com/2019/03/beginner-sourdough-starter-recipe/
Excellent summary of how I make sourdough bread, citing the original sources that the protocol below modified (Tartine bread recipe that Chad Robertson shares in his books Tartine Bread and Tartine No. 3.): https://www.thekitchn.com/how-to-make-sourdough-bread-224367
Good video for a few extra pro tips (some incorporated in my summary below): https://www.youtube.com/watch?v=BJEHsvW2J6M
WATER
For everything below, I use tapwater that has rested for a day or so in a Brita so the chlorine has a chance to evaporate. Bottled water also good. I’ve occasionally used a bit of tapwater for starter, leaven, or bread and everything still works. Don’t overthink it.
STARTER
Starter can be left on the counter for frequent access to start making bread by feeding every day or two but I prefer to store in the fridge, feeding once a week. I find that starter on the counter, fed so often, increases in volume too quickly and I am not a fan of daily starter pancakes or compost. If in the fridge, best to put on the counter 2 days before making bread, feeding once when first brought out and then again the morning before leaven inoculated in the evening.
Note that after a week in the fridge, the starter will have watery “hooch” on the top, which is a yucky waste product. Spoon or pour that out before feeding.
Although starter can be fed 100% all purpose unbleached flour (or simply "bread flour"), I always feed from a ziploc baggie of 50/50 whole wheat/unbleached because my bread is always made with some whole wheat. I figure it makes sense to keep them active on whole wheat all the time.
My starter is kept in an old sauerkraut jar but any container with a loose lid is fine. When I feed, I typically add 1/3 cup of the 50/50 flour mix and then "eyeball" ~80% or 90% of that same 1/3 cup by volume. Mix well and put back on the counter or in the fridge.
MAKING BREAD
STEP 1: Make the leaven (usually after 9 pm the night before making bread)
Add 1 tablespoon starter, 75 grams (1/2 cup) of a 50/50 whole wheat/unbleached mix (same as used for starter), and 75 grams (1/3 cup) water. Mix well.
Leave overnight in a cereal bowl with a plate inverted on top to keep moisture in. It will look a bit bloated and bubbly in the morning. Websites talk about float tests you can do to make sure ready. Don’t worry, it’s ready if you see a few bubbles.
The purpose of making leaven is to scale up the microbes from the starter culture so there are enough of them to tackle all the flour you will throw at them the next day. Some “simple time saver” recipes for sourdough you might find online speed everything up by using a cup (a lot!) of starter to jump start the bread making process. The bread you get from these much easier recipes is edible, but not nearly as good.
STEP 2: Make dough (morning)
Scoop all leaven into a mixing bowl. Add 475 grams (2 cups) of water to the leaven and mix with a spoon or spatula until "dissolved".
Add 700 grams (5 1/2 cups) total of an all-purpose ubleached flour and whole wheat flour mix. I’ve tried many ratios (from 100% whole wheat to 100% unbleached) and have settled on my favourite: I use 500 grams ubleached all-purpose and 200 grams of whole wheat. Mix with spoon and then hands until it’s a shaggy dough with no more fluffy flour in the bowl.
Let it sit for 30 min to 4 h in covered bowl (cover bowl with plastic, towel, or plate) for the process of autolysis (enzymes get to work breaking down flour components). Lots more info on the importance of autolysis here: https://truesourdough.com/sourdough-autolyse-is-it-needed-if-so-how-long/
Dissolve 1 tablespoon (17 g) of kosher salt (or sea salt - not table salt) in 50 grams (1/4 cup) of warm water and swirl until almost completely dissolved.
Add salt water to dough and pinch, squeeze, and fold to mix. It will now be wet.
Pull and fold over 4 times with 1/4 rotations between folds. Repeat every half hour for a total of 6 fold actions over 2.5 hours. You can miss a fold action and be flexible on timing here - not a big deal.
Once finished with the final fold action (2.5 hours after adding salt water), let sit for 30-60 minutes until puffed.
Move onto a floured surface and split in half. Sprinkle a little flour on.
Shape dough into loose rounds, pulling bottom to top, rotate.
Sprinkle a little flour and rest dough balls on counter for 30 minutes, covered with a towel.
Prepare mixing bowls with flour-sprinkled parchment paper on top (to receive loaves once shaped).
STEP 3: Shape loaves (afternoon)
Shape the loaves. Dust the top of one of the balls of dough with flour. Flip it over so that the floured side is against the board and the un-floured sticky surface is up. Shape the loaf much like you folded the dough earlier: Grab the lip of the dough at the bottom, pull it gently up, then fold it over onto the center of the dough - hold for a second for it to attach. Repeat with 90 degree turns until the loaf seems “about right”.
Cup the loaf and turn it over to sit fold-side-down on the parchment paper, which will then sink into the high-walled mixing bowl. Cover with a plate (or plastic wrap).
Repeat with the second ball of dough.
Let the dough rise at room temperature until they look billowy and poofy, 3 to 4 hours. Alternatively, place the covered basket in the refrigerator and let them rise slowly overnight, 12 to 15 hours. If rising overnight, bake the loaves straight from the fridge; no need to warm before baking.
STEP 4: Baking (early evening; or next morning if preferred)
Heat the oven to 490°F and, while heating, place a Dutch oven with lid in the oven. If you have two Dutch ovens, two loaves can be baked at the same time.
Right before transferring loaf to Dutch oven, score the top with a razor blade or sharp knife. A straight cut off center from one side to the other works great. Try to score at a slight angle, so you're cutting almost parallel to the surface of the loaf; this gives the loaves the distinctive "shelf" along the score line.
Carefully remove one of the heated Dutch ovens from the oven and remove the lid. Transfer the scored loaf to the Dutch oven by holding the parchment corners and lowering into the Dutch oven.
Repeat with the second loaf (if you have two Dutch ovens).
Bake the loaf (or loaves) covered for 20 minutes. Reduce the oven temperature to 425°F and bake another 10 minutes. Resist the temptation to check the loaves at this point; just reduce the oven temperature to 425°F. Bake another 10 minutes. Remove the lids from the Dutch ovens, place ovens on a cookie sheet, then continue baking open for 20 minutes. The idea is to continue baking uncovered until the crust is deeply browned; aim for just short of burnt. It might feel a bit unnatural to bake loaves this fully, but this is where a lot of the flavor and texture of the crust comes in. 20 minutes works for me.
Transfer loaves to a cookie wire rack by carefully lifting by the corners of the parchment (it will tear easily - be gentle and slow).
Repeat with other other loaf if only using one Dutch oven.
I usually place cooled loaf in large ziplock bag and throw in the freezer, or leave on the counter until morning if slicing the next day. Freezer storage doesn’t affect the flavour/taste at all negatively but the crust will eventually lose its crispy "crackliness" no matter what you do. It will still taste good so that’s not a big deal. Bread left in the bag on the counter and sliced/used daily will last ~5-7 days before becoming a bit stale or showing signs of mold. One option is to slice the bread before putting in freezer bags so individual slices can be pulled out to make toast.
Note: I have two Dutch ovens so I do the entire process above with two batches and make 4 loaves at a time. Doing this once or twice a week produces all the bread our family can eat with a few gift loaves to spare.
Note: This may seem like an overwhelming number of steps. But, trust me, the entire process can be done completely from memory after a short time and eventually it seems easy.
Enjoy!