A light at the end of the tunnel!
...after 24 hours (day 7, total), the seed culture was sufficiently fermented and ready to (finally) be converted into the mother starter:
At this point, the seed culture is chock full of wild yeast and bacteria, but is incredibly weak from all the acid buildup and the perpetual breakdown of proteins and starches. How to remedy the situation? Feed the bitch. Ratio of seed culture: flour: water (in grams): 113:340:255. The mother is mixed, kneaded for 2 minutes (again, refer to Reinhart for specific details).
It hangs out in an oiled bowl for 4-8 hours, until it doubles in size, has a 'pleasant acidic aroma' and looks like this.
At this point in time, the mother is ready to begin doing her job ('fertilizing' some dough).
...and moves into her new home, a state-of-the-art Gladware container.
Now arrives the moment of truth, the litmus test on whether this week of coaxing the mother into being was worth the effort: a loaf (or two) of Pain au levain (which is just French for 'leavened bread.'). As Peter Reinhart mentions, Pain au levain "is generally considered to be the gold standard for wild yeast breads, though opinions do vary widely - and are strongly held." (Thus the adventures in mother starters.) Pain au levain is not really one specific recipe, but rather a genre of breads consisting primarily of white flour, supplemented with whole wheat, rye or multigrain flours, made with wild yeast starter (although some do supplement further with commercial yeast. Not here). I will experiment with Reinhart's recipe from Artisan Breads Every Day. And - shockingly - this is another multi-day affair.
Day 1: Sourdough starter
71 g (1/3 c) mother starter
142 g (1c + 2T) unbleached bread flour
85 g (2/3 c) whole wheat flour
151.5 g (2/3 c) H20 @ room temperature
Combine all the ingredients in a mixing bowl, stirring for 2 minutes. Dough should be tacky or slightly sticky. Transfer to a lightly floured work surface and knead for 30 seconds. Place in a clean, lightly oiled bowl, cover loosely and leave at room temperature for 6-8 hours until it increases to about 1.5 times original size. Put in fridge overnight (or up to 3 days).
After 24 hours, the starter should look like this:
Day 2: Make the dough
All of the sourdough starter
312 g (1 c + 6 T) lukewarm water (around 35C)
454 g (3.5 c) unbleached bread flour
17 g (2 3/8 t) salt (or 3.5 t coarse kosher salt)
Cut the starter into 10-12 pieces, add water and mix for about 1 minute to soften the starter. Add the flour and salt and mix for another 3 minutes. let the dough rest for 5 minutes. Knead by hand for 3 minutes, adding more flour or water as needed to make a soft, supple and tacky (but not sticky) ball of dough. Form into a ball. Let the dough rest for 10 minutes and then stretch and fold: "either on the work surface or in the bowl, reaching under the front end of the dough, stretching it out, then folding it back onto the top of the dough. Then do this from the back end and then from each side, then flip the dough over and tuck it into a ball." Cover and let it rest for 10 minutes. Repeat two more times. Form the dough into a ball, place it into a clean, lightly oiled bowl large enough to allow it to double in size and cover tightly. Let it sit at room temperature for 2 hours and then refrigerate overnight (or up to 4 days).
Day 3: Baking Day
Remove the dough from the refrigerator 4 hours before you plan to bake. After 2 hours, shape it into a boule or 2 smaller ones (as I did). Let it proof for 2 hours (seam side up). Preheat oven to 500F about 20 minutes before baking, place shelf in bottom third of oven. Just before baking, transfer dough (seam side down) to a baking sheet with parchment or a Silpat and score with a lame or serrated knife.
Place in oven, pour 1 c hot water into a steam pan below dough. Reduce heat to 450F. Bake for 12 minutes, rotate pan 180 degrees, continue baking for 15-25 minutes. Finished loaves should be a rich caramel color in crust, sound hollow when thumped and have an internal temperature of about 200F. Cool on rack for at least 1 hour before slicing. Enjoy the hell out of it.