Never Give Up Sourdough
I post this for 2 reasons:
1) I thought this sourdough was going to bomb, but it didn't. Never give up on your sourdough.
2) I made several changes to the recipe I have been using for 4 months, and I learned a lot. Maybe you will too.
Most important thing I learned: Never give up on your sourdough. (I mean the loaves, not the starter.)
This is a somewhat long story, with a few unusual twists to tell, so I apologize for the wind and will understand if you skip ahead.
As I was planning for this bake I was thinking about my previous sourdough experience. (I make a version of Jeffrey Hamelman's Vermont Sourdough, recipe already on TFL.) For the previous bake I made the final build of the levain at night, and mixed the dough early the next morning. An overnight retarding of the loaves would have been overlong, so I opted for same-day baking. When I took my shaped loaves out of their bannetons, they reeelaaaaaxxxxed. Into the oven they went, but their oven spring was underwhelming. The taste was tangy, wonderful, but the crumb was not open and airy as usual.
This time I was planning a few changes. I was concerned that the main issue had been gluten development. For starters I figured I'd go back to early-morning final levain build and mixing the dough in the afternoon, which would allow for overnight retarding.
On top of this I was considering something Mike Avery recently posted in a response, where he explained that autolyse does NOT involve yeast, commercial or wild. I thought that mixing the dough in advance, without leaven, might help build gluten, which I speculated had been at fault for my flattish loaves. I knew also that there would be some enzymatic action as a result of this autolyse process, so I hedged my bets and decided to let the dough sit for just 3 hours.
When I added my levain to the autolyse in my mixer, it was very, very wet. OK, I should have broken up the dough first, that became clear. But I figured I could still mix and distribute all the ingredients sufficiently. After 3 minutes the dough was still sticking both to the bottom and the sides of my mixer's bowl. (Fortunately, this no longer daunts me, thanks to the video of M. Bertinet that holds99 recently provided this link for: http://www.gourmet.com/magazine/video/2008/03/bertinet_sweetdough 
Also, I wasn't tempted to add flour, having seen M. Bertinet say about such glop: "This is what dough should look like.")
I took the sticky mass and started throwing it down and folding it over. I "cheated" only a little bit with one dusting of flour. Within a few minutes, remarkably, the dough was coming together. There were a few pea-sized lumps but I flattened them when I found them. Then I let the dough ferment for almost 3 hours, with 2 folds to build strength. It still seemed loose and weak and I admit I was concerned.
I shaped 2 boules and put them in bannetons, which I had dusted (mistakenly) with AP flour instead of semolina as usual. I let the loaves proof for exactly 1 hour and put them in my refrigerator, which can hold between 43 and 44 dF, to retard overnight.
In the morning my heart sank. The loaves had barely risen. Never give up on your sourdough. Next came another change I had decided to try: I wasn't going to let the loaves wake up for several hours before baking. I pre-heated my oven to 480 dF for an hour, putting a steam pan in at the 45-minute mark. Hamelman, in Bread, makes a point that sometimes waiting for his loaves to warm up has rendered flat loaves, and thus unlike others he is not against more or less immediate baking. So that was what I was going for.
And that turned out to be a good choice. First, I had trouble getting one loaf out of its banneton (curse that AP flour). Still, for all the manhandling, it came out and held its shape! The second loaf came out more easily, but it looked puny. Still it held its puny shape.
Using my (Pure Komachi) tomato knife I slashed the first loaf with ease and confidence. The dough held: it was still cool! Into the oven und spritzen. Slash the second loaf, into the oven und spritzen again. The first loaf kept its poise, so I thought it would be OK. The puny second one sagged a little on the baking stone, and my confidence sagged with it.
At this point, if you're still here, it occurred to me that because the loaves were cool, they could handle more spritzing than usual. This turned out to be true. I turned the oven down to 460 dF and sprayed the oven 4 times over the space of 8 minutes. The crust hadn't yet turned color so I figured keeping the oven moist until I saw color would help, and it did. Still, the second loaf looked saggy. I sprayed it one more time and closed the oven, expecting the worst for that one.
Five minutes later, when I opened the oven door to turn the loaves and take out the steam pan, loaf 2 was puffed up almost like a volcano! I thought it had blown up inside, full of the air holes "where the baker sleeps at night." I turned the oven down to 440 dF and waited. Something else I learned: if you put your dough in without letting it warm up for hours, it needs to bake longer. OK, duh. So, as with being able to spritz for longer, I kept the loaves in the oven for longer, which gave me more control over temperature. At the 30-minute mark I took instant temperatures: the first loaf was only around 165 dF and the second was a little soft where the lava comes out, so I didn't bother poking it.
Ten minutes later I took temps. Loaf 1 was ready, at 208 dF. Loaf 2 was 198 so back in it went. I turned the oven down to 410 dF and gave it 3 minutes. Then I took it out and they both got 3 hours cooling time.
At this point I thought loaf 2 was a mess inside and I didn't figure it was worth showing it. Loaf 1 was beautiful inside and was half-gone in short order. When I started cutting into loaf 2 I realized I had totally missed the boat. Though it hadn't risen much at all in the fridge, and had sort of sagged in the oven, it made an amazing comeback. And I am thinking that comeback was because it was cool when it hit the oven, and I kept it moist long enough for the yeast to stage their heroic last stand.
Here's a picture of the crumb of Loaf 2:
Sourdough crumb: Never Give Up Sourdough
Next time: I will repeat my sourdough with the autolyse, but I will use only half the flour for that, and I will break up the dough into pieces when I mix everything together. Otherwise, I'm sticking with my story.