Step 1

Levain – 9:00 p.m. (overnight)Mix the levain ingredients in a jar and leave them covered at a warm temperature, 74-76°F (23-24°C), to ripen overnight.

Step 2

Mix – 9:00 a.m.Cut the butter into ½-inch pats. Set aside. To the bowl of a stand mixer fitted with the dough hook attachment, add the flour, water, milk, honey, salt, and ripe levain. Mix on low speed (STIR on a KitchenAid) for 2 to 3 minutes until the ingredients come together and no dry bits remain. Next, mix on medium speed (2 to 3 on a KitchenAid) for 4 to 5 minutes until the dough smooths and begins to cling slightly to the hook. Turn the mixer on low speed (STIR on a KitchenAid) and mix for 2 to 4 minutes until the dough gains more strength and begins to cling once again to the dough hook. Next, with the mixer running, add the room temperature butter, one pat at a time, waiting to add each pat until the previous one is fully absorbed. Adding all the butter will take 5 to 8 minutes. Transfer the dough to a bulk fermentation container and cover.

Step 3

At a warm room temperature, 74-76°F (23-24°C), bulk fermentation should take about 4 hours. Give the dough 3 sets of stretches and folds at 30-minute intervals where the first set is 30-minutes after bulk fermentation start.

Step 4

Scrape the dough out of the bulk fermentation container, divide it directly in half, and preshape each half into a taut round. Let rest for 30 to 35 minutes.

Step 5

Shape – 1:45 p.m.Shape one round into a tight tube, and place in the pan seam side down. Repeat with the other piece of dough. Cover the pans with a large, reusable plastic bag and seal.

Step 6

Proof – 2:00 p.m. to 4:45 p.m.At warm room temperature, 74-76°F (23-24°C), this dough should take 2 hours and 45 minutes to fully proof. If your kitchen is cooler, expect it to take longer.

Step 7

Bake – 4:45 p.m.Place an oven rack in the bottom-third of the oven, and preheat the oven to 425°F (220°C).Place the pan into the oven and bake for 15 minutes. Reduce the oven temperature to 350°F (175°C) and bake for an additional 30 to 35 minutes. The loaves should have internal temperatures of around 204°F (95°C). Remove the pans from the oven, uncover, and let the loaves rest in the pan for 10 minutes. Then, turn the loaves out onto a wire rack and let cool completely, 1 to 2 hours.