Step 1

Before bedtime, build your leaven. Weigh 100 grams of lukewarm water in a mason jar and add 50 grams of your healthy, active starter, which you fed this morning (8-12 hours ago). Don't use freshly fed starter, it is not mature enough.

Step 2

Swirl the jar to incorporate the starter. Add 50 grams whole wheat flour and 50 grams white flour (all-purpose or bread flour). Stir with a butter knife or spatula until mixed well. Make sure no dry flour remains.

Step 3

Place the lid lightly on the jar – don't screw it on! – and leave on the counter to ferment overnight.

Step 4

Place your mixing bowl on the scale and weigh 640g of the water (save 50g) and 184g of your leaven. Using your hand, incorporate the leaven a bit by squeezing it through your fingers. Use the rest of your leaven in discard recipes, or simply throw away.

Step 5

Add both flours and mix together with your hand. Mix until you don't see any more dry flour in the bowl. The dough will become sticky, so it's useful to keep one hand clean. Dunk your clean hand in water, and remove the sticky dough from your other hand. Then dip your dough spatula in water and scrape the edges of the bowl, making it as clean as possible.

Step 6

Cover the bowl with a clean kitchen towel or plastic and let the dough rest for 30 minutes. This is called the autolyse, which allows the flours to absorb the water, activating the enzymes which begins the gluten development. This step is critical and cannot be rushed.

Step 7

After the autolyse, sprinkle the salt over the dough and then add the remaining 50g of water. Poke your fingers into the dough to press some salt deep inside, then fold over itself about a dozen times or so to incorporate the salt. Cover the bowl again; the bulk fermentation has begun. Set your timer for 30 minutes.

Step 8

The bulk fermentation takes four hours. During the first two hours of the bulk fermentation, the dough must be folded four times, or every 30 minutes. This is similar to kneading but is much more gentle to preserve the natural gases that become captured in the dough, and is much easier on the baker.

Step 9

To fold the dough, first imagine your bowl as a compass: the edge furthest from you is north, the right edge is east, the closest edge to you is south, and the left edge is west. Dip your hand in water and reach under the dough at the east point. Grabbing it gently but firmly, pull the dough out to the east and then fold it over itself toward the west. Rotate the bowl a quarter-turn, and repeat. Do this for each "corner" of your compass, then cover with a kitchen towel. These are called stretch-and-folds.

Step 10

Set your timer for 30 minutes, and repeat the process three more times.

Step 11

Your dough now gets to rest, covered and untouched, for 1 1/2 – 2 hours. During this time, flavor and strength is developed, so don't rush this step.

Step 12

After the bulk fermentation, pull all the dough onto a floured work surface using a dough spatula. With your bench knife, cut the dough into two even pieces.

Step 13

The pieces now need to be pre-shaped. Working with one piece at a time pull the west side of the dough out and fold it toward the east. Then pull the east side out and fold it over and toward the west. Then grab the north side and fold it up toward the south, then roll the dough loosely toward the south and let rest on its seam. Do the same for the remaining piece, then lightly dust both with flour and cover with a kitchen towel. This prevents a skin from forming on the outside of the dough. Let rest for 30 minutes. This is called the bench rest.

Step 14

For the final shaping, care must be taken not to deflate the dough. Gently rub off any excess flour – the top of the dough will become the inside of the loaf, so you don't want any extra flour inside. First, gently pull out on the corners to make a very rough rectangle of dough. Just as in the pre-shaping, pull the west side of the dough out and fold it toward the east. Then pull the east side out and fold it over and toward the west. Stretch the north side up and fold down toward the south, then roll the dough down like you're rolling a yoga mat. You will hear and feel gas bubbles popping; this is okay. Repeat for the remaining piece.

Step 15

Lightly grease each bread pan with olive oil or butter, and place each dough roll into the pans. Now begins the final rise. Cover with plastic or place in a grocery bag, and put both pans into the refrigerator overnight. This is called cold-proofing. The plastic is used to prevent fridge odors from absorbing into the dough. The dough will continue to ferment slowly. You can leave your dough in the fridge for up to 48 hours, but I recommend baking around 18 hours if possible.

Step 16

In the morning, create a steam tray. Place two or three old kitchen towels in a cookie sheet and soak them under the faucet, filling the pan about halfway up with water. Place your steam tray on the lowermost rack of the oven and preheat at 400*F for at least 30 minutes. KEEP AN EYE ON THE LEVEL OF WATER IN YOUR STEAM TRAY. If the water boils dry, your towels will burn. To add more water, use hot tap water and pour from a watering can or a large pitcher.

Step 17

When your oven is preheated and steamed, pull the bread from the refrigerator and remove the plastic. Brush the tops with egg white if you'd like a softer, dark brown crust. Add poppy seeds, rolled oats, or any other toppings on the egg wash if desired. Place bread pans in oven and bake uncovered with steam for 20 minutes.

Step 18

After 20 minutes, carefully remove the steam tray and vent the oven. Rotate your bread pans 180*, then bake 30-35 minutes more.

Step 19

Remove the bread from their pans by tipping upside down, then place loaf directly on oven rack and bake for 5 minutes more.

Step 20

Remove and allow to cool for at least two hours. Slice and enjoy!