Boil 2 cups of water and pour over the polenta. Stir and set aside to cool completely. In a 400 degree oven, toast the pumpkin seeds until they are a bit brown and crackling, about 10 minutes. Stir once or twice.Once the polenta is cool, add the pumpkin seeds, rosemary and olive oil. This will be our addition to the bread and will be added 30 minutes after the first stretch and fold.
Now that the leaven is done (see Day 7), let's do the float test. Fill a small bowl with water and drop a teaspoon of leaven in the water. If it floats, then the leaven is ready and there is enough fermentation to produce a good loaf. If the spoonful of leaven does not float, put the leaven in a warm spot for another 30 minutes or so, and then try the float test again. Turn the oven on low for a minute or two, turn it off, open the door and set the leaven inside for a few minutes. That might speed up the process. Make sure the inside of the oven is not above 80 -85 degrees F.
Once the leaven has passed the float test, it's time to make the dough. Using your kitchen scale, add 700 grams of 80 degree water to a large mixing bowl. Spoon in the 200 grams of leaven and push it around with a spoon to incorporate. (The unused leaven is now your starter.)Add the flour and stir to completely incorporate the flour. Use a large spoon or your hands to mix. Cover with a kitchen towel and rest for 30 minutes. This is the autolyse stage, where the flour, yeast and water become fully hydrated.
After 30 minutes, dissolve the salt in the remaining 20 grams of water and add to the dough. Use your hands and smoosh and squeeze the dough to work in the water and salt. Cover with a kitchen towel and let rest for 30 minutes.
Now we begin the turning and stretching phase: The video from Day 7 provides an excellent demonstration of this technique (at 5:59). Holding the bowl steady with one hand, use the other hand to scoop under one edge of the dough, grab a hold and pull it out to the side and fold it back on top. Rotate the bowl a bit and do the same technique. Keep rotating the bowl and stretching and folding into the center until you have gone all the way around the bowl. We do this instead of kneading the dough.
Do the first turn and stretch. Wait 30 minutes and then add the polenta mixture. Smoosh and really work into the dough. Set aside for 30 minutes and proceed with turn and turn 3 more times at 30 minute intervals.
After the stretching and folding stage, rest for 30 minutes.Flour a large board. Turn the dough out onto the board and cut in half with a bench cutter. (Remember, this recipe makes two loaves of bread.)We want to create some surface tension on the top surface of each loaf. Use your two hands to curl the edges of the dough underneath. (Again, the video from Day 7 gives a good visual of this process. at 7:15).Once the two loaves have been shaped and surface tension accomplished, cover with a kitchen towel and rest for about 30 minutes. For the next step, you will need either two bannetons or two medium bowls covered with a cotton towel. Make sure to coat the bannetons or towels with a layer of flour to prevent the dough from sticking to the fabric.Sprinkle some flour on top of each loaf. Flip the loaf over on the board, flour side down, and grab the right end of dough and fold over to the center. Grab the left end of dough and pull and fold it over to the center. Grab the edge closest to you and stretch and pull it up to the center. Finally, grab the top of the dough and pull it down and under the front of the dough. What we are doing here is shaping the loaves and creating more surface tension. Again, please watch the video from Day 7 at 8:36).Repeat for the other loaf and then place each loaf in the banneton or cloth-lined bowl, smooth, floured side down. Note: (I have had the dough stick to the cloth before, but do not fret! Just pinch the dough off the cloth and carry on.) At this point, you have two choices. 1) Let loaves rest in the bannetons for 4 hours in a 75-80 degree room. Or 2) place them in the refrigerator and let them rest overnight and bake them the next morning. This slow refrigeration- fermentation gives more depth of flavor to the dough and gives you a bit more freedom in your schedule.If you choose to bake them the same day, if your room is cooler than 75 or 80 degrees, (65 - 70 degrees). let the loaves rest for an additional 5-7 more hours before baking. After some time, you will develop an instinct as you watch how your dough behaves. Preheat oven to 500 degrees F.To prepare the dutch oven: tear off a piece of parchment paper large enough to fill the dutch oven. With your hands, spread a thin coat of olive oil over the parchment paper, and place the parchment paper, oiled side up, into the dutch oven. I use the coating of olive oil because I have had the loaf stick to the parchment paper during cooking and that is just no fun.Next, turn each loaf into a dutch oven. (the dough will be touching the oiled side of the parchment paper). If you only have one dutch oven, you can cook one loaf at a time. There is much debate over which is the best vessel for baking the loaves. Many folks love the Cast Iron Combo Cooker. I like to use the CorningWare dutch oven with the glass lid. (see notes below).You don't have to preheat the dutch oven.Scoring the loaves: Once your loaves are in the dutch oven, use a razor blade to score the top of the loaves. You can make an X shape or cut a square shape on top of the dough, about ½ deep. This allows steam to exit the loaves so they won't split open during baking. (video at 10:00).Place the loaves in the oven, turn down the heat to 450 degrees F. and cook for 20 minutes with the lid on. Then remove the lid and cook for 30 more minutes.Remove the loaves- As soon as they are done baking, take the loaf out of the dutch oven and cool for at least 1 hour before eating.If you just can't wait, and cut it open while it is still piping hot, the inner part of the bread will be nice and creamy. Go ahead and enjoy it!Once the loaves have cooled completely, put them in a paper bag and then in a plastic bag. This way they the loaves will last for up to a week.