for the levain: 100 g mature active sourdough starter 400 g unbleached all-purpose flour 100 g whole wheat flour 400 g lukewarm water

for the final dough: 900 g unbleached all-purpose flour 700 g water (warmed to about quite warm) 20g table salt 500g (about 1 pound) bacon, fried to crispy, and then crumbled (think this is 500g uncooked, I’m not sure, I made like a pound and a half) 4 T reserved bacon fat 305 g of the levain . Mix the levain ingredients in a medium bowl, cover with plastic wrap, and let sit for about 10 hours, until bubbly. In a large bowl mix the flours and water by hand until just incorporated. Cover and let it rest for 20 to 30 minutes (that is the autolyse step). . Sprinkle the salt all over the flour mixture, then add the levain. Using wet hands to prevent the dough from sticking, mix the dough by pinching it to distribute the salt. Cover and rest for 10 minutes. . Spread the bacon fat over the dough and add the crumbled bacon. Using the pincer method alternating with folding, mix all of the ingredients in the bucket. Cover the dough with plastic wrap, and let it sit for 30 minutes. In the next 2 hours, stretch and fold the dough 4 times, every 30 minutes. Cover and let rest at room temperature for 12 hours, until about tripled in volume.

Gently shape the dough into a loose boule. Flour a banneton, shape the dough into a medium tight ball and place it seam side down into the proofing banneton. Cover with oiled plastic wrap. Let the loaves proof for about 4 hours, depending on the room temperature.

About 45 minutes before baking, heat the oven to 475 degrees F with an empty covered Dutch oven placed on the middle rack.

Remove the Dutch oven from the oven and remove the lid. Place a piece of parchment over the banneton with the proofed bread inside, and a flat baking sheet over it. Flip the dough over, remove the basket, and place the shaped boule in the Dutch oven using the parchment to help move it. The paper can stay in during baking. Cover the Dutch oven and place it in the hot oven. Wet the lid of the Dutch oven, and quickly use it to cover it. Alternatively, you can use your own favorite method to generate steam during baking.

Bake covered for 30 minutes, and then uncover it and bake it for 15 to 20 minutes more, until the interior of the bread reaches 205 to 210 degrees F and the bread is a deep brown.

[My ingredient alterations in italics]

Bacon as an inclusion sounds great, but I’m wondering what the 4Tb bacon grease did to your crumb structure? I’m only used to doing lean doughs with sourdough.