In a medium size mixing bowl, combine the water, unbleached all purpose flour, and pinch of dry active yeast. Mix until thoroughly combined, and then cover the bowl with a clean kitchen towel, or plastic wrap. Let ferment at room temperature for 12-14 hours. The poolish should look be bubbly, jiggly, and puffy.

To a large mixing bowl, add the all purpose flour, whole wheat flour, wheat bran, and 1 gram of yeast. Mix to combine. Pour all of the water around the edge of the bowl with the poolish. This will help loosen up the poolish. Pour the watery poolish into the bowl with the flour mixture (it should slip right out!). Use your clean hands to mix and pinch the dough together. It will be sticky, but use a spatula or a bench scraper to clean them off. Cover the dough with a clean kitchen towel or plastic wrap, and let sit at room temperature for 30 minutes.

Add the kosher salt to the dough, pinch it into the dough thoroughly. Then stretch and fold the dough, stretching the sides of the dough up, and folding it over itself. Work your way all the way around the perimeter of the bowl, then plop it over. Cover, and let rest for 30 minutes.

Stretch and fold #2. Cover, and let rest for another 30 minutes.

Stretch and fold #3. Cover and let bulk ferment for 2-3 hours at room temperature.

Pour the dough out onto a lightly floured surface. Pull the 4 sides of the dough into the center. Then pull the corners into the center. Turn the dough over (seam side down) and pull the dough toward you to perfect the boule shape.

Pour about 1 cup of wheat bran into a shallow bowl. Spray the dough with water, and dip the douugh into the wheat bran to coat the outer crust. This step is optional, but the wheat bran toasts and it adds a really nice nutty flavor.

Place the boule of dough, face down, in a floured proofing basket. Cover with a towel, and let proof at room temperature for 1 - 1½ hours.

Meanwhile, preheat the oven to 450°F. Place a Dutch oven inside to preheat as well.

Remove the preheated Dutch oven from the oven. Remove the lid. Cut a sheet of parchment paper in half. Place the parchment on top of the proofing basket, then invert the basket, so the dough is on top of the parchment paper. Slash the top of the loaf with a lame or sharp chef's knife.

Place the parchment and the dough into the Dutch oven. Cover with the lid, and place in the oven.

Bake for 25 minutes with the lid on. Then, remove the lid, and bake for another 22-25 minutes. The crust should be deeply golden brown.

Allow the bread to cool completely on a cooling rack for at least 1 hour before slicing.