Really proud of the rise and crumb on this one - I had been on a quest for a light, springy whole wheat loaf as I remained stubbornly opposed to the fact that 100% whole wheat meant necessarily dense and heavy crumbs.
Pleased to say this recipe worked out well (adapted from Full Proof Baking's wonderful blog) - she recommended doing a cold, overnight bulk fermentation and I think that really did the trick here. Very minimally handled overall.
Recipe as follows:
50% Red Fife
50% Whole Wheat White Flour
8% Whole Wheat Levain (fed at a 1:5:4 ratio so a bit stiffer than usual)
2.2% sea salt
Mixed levain 4 hours ahead of autolyse, which sat for another 2 hours until levain was peaked and flour was fully hydrated. I used cool water here as recommended to slow the dough down. Added levain to dough along with salt, and then did a quick stretch and fold on the counter top to form a ball and transferred to bulking dish.
I don't have a proofing box, so I used a cooler box with a freezer pack or two to make a cooler environment than my kitchen. She recommended 68F but I couldn't get it quite there so mine sat at ~54F overnight for about 12 hours.
In the morning the dough was fluffy and airy and very soft, but had seemed to rise well. I let it sit for an hour longer at ~68F (cooler warmed up) since it was colder overnight, then did 1 coil fold to pre-shape. Waited another hour then final shaped into batard and popped it into the fridge for another 5 hours.
Baked 20 min covered at 450 then 25 min uncovered at 425.