To prepare the mother, 2 days before the intended bake, add 100 g water and 100 g flour to 100 g of your mother. The next day, add 300 g water and 300 g flour to the 300 g of mother. The next day, separate out 100 g of the mother and reserve for next project. Use remaining 800 g in this recipe.
Mix all the ingredients for about 10 minutes and turn out onto floured workspace.
Fold the dough a few time, shape into a bowl, and put into a covered container. It will be about 200 L in size.
Allow to rise until doubled in bulk. The cooler the area, the longer it will take and the more of a sour taste will develop. This is a personal preference. In a warm area, the yeast will thrive and rise faster. In a cooler environment, the bacteria will thrive and develop more of a sour taste. Either way, it should double in bulk.
Preheat the oven to 425 F.
Divide dough into two loaves. They will be just under 1 kg each.
Shape each into a loaf shape and set to rise on a linen lined board. (I have left out pictures of the process of shaping. I pat it out and fold into thirds with the bottom being more narrow than the top. I then fold the bottom third onto the middle third. Finally, I tightly roll the dough up to the top. Let it rest a bit and then roll to desired shape.)
Allow to raise until double in bulk. In the picture, I probably should have let it go a little more.
Place the load on a peel dusted with coarse cornmeal, and use a lame to score the loaf from end to end. You can use a cooked corn starch solution or egg white to base the loaf to hold seeds (preferably caraway) on the outside. Be sure to avoid any liquid on the peel.
Bake in a 425 F oven for about 25 minutes, until internal temperature is 200 F. During bake keep the oven air moist. This can be done with spraying water into the oven, placing ice cubes in an oven proof pan, add boiling water to an oven proof pan, etc.
This loaf isn't necessarily the desired result. I didn't let it raise enough, and the oven spring opened up the score too much. But it sure did taste good!