Very pleased with the outcome – decent oven spring and nice holey crumb, esp. for a 100% whole grain bread. Also - tasty! I made this loaf using the long cold fermentation approach described on the recipe page for original no-knead sourdough. I mixed the dough up Thursday morning using about 40g of whole wheat starter (a little over 1/8 a cup). Performed 3 rounds of stretch and folds per Eric’s instructions with the spelt recipe. Let it ferment in the refrigerator for two days, and took it out yesterday morning to finish the bulk ferment on the counter. Did another two stretch and folds after the dough warmed up a bit.
I intended to bake it last night, but after sitting out for about 12 hours the dough did not seem ready. At about 14 hours it was ready (smooth, shiny, kind of domed top surface, and I saw lots of air holes through the clear glass of the bowl), but by then it was time for bed. So I pre-shaped and rested it, shaped it into an oblong, placed it in a floured banneton and then into the fridge overnight. I baked it this morning in an oblong clay baker, then let it cool for 1 1/2 hours before slicing and eating.
Tastes great and has a slightly more sour tang than a loaf made with the basic 100% whole spelt sourdough recipe (1/4 cup starter, bulk fermented 12-14 hours at room temp, then proofed 90-120 minutes at room temp and baked).
I’m not sure I will go this route again (long fermentation), as I’m not sure it adds much in the way of flavor. On the other hand, knowing I can stick the dough in the fridge for extended periods of time makes bread-baking more convenient in terms of my schedule. The bread is delicious either way.