I hadn't baked for a while and decided to make Field Blend # 2 form K. Forkish's FWSY.
I prepared the levain using 100g active rye sourdough starter and used Red Fife flour instead of the wholewheat.
Then I realized that the recipe calls for only 360g of the levain, and that 640g would be discarded.
Dang! As others said this sounds incredibly wasteful. So I thought of using the 640g of leftover levain.
It had risen nicely over 7 hours or so and looked almost like a poolish.
I took the 640g, added 100g Red Fife flour, 100g dark rye flour., and 160 g H2O. This gives an almost 80% hydration dough I believe. I did four S&Fs in th bowl over the next hour and let the dough rest for another hour. It was very slack and pretty much impossible to shape. I slid it into an oblong banter and placed it in the fridge overnight. I baked it straight out of the fridge in an oblong cloche. I didn't slash it. It came out pretty nice and it takes excellent.
In the future I'll think a bit more ahead but this 'experiment' turned out rather well.
(As an aside, I don't know what I'm doing wrong. I took this picture with an iPhone and for some reason the picture is rotated when I upload it. Any suggestions?