the proportions for this recipe originated in Rose Levy Beranbaum's recipe for lighter-than-air focaccia in "The Bread Bible." I became aware of it because reviews of the book declared the recipe impossible and clearly a mistake -- a challenge I could not resist. it was so called because the proportion of flour to water was extraordinary. where a typical bread is around 65% water to flour, hers was 113.5%. not a typo, the weight of water exceeds the amount of flour.
several things about the original were not to my taste. for example, she adds sugar; she uses commercial yeast; and she uses plain unbleached flour. So, I've been experimenting with alternatives for several years now, and have settled on my own version. I hesitate to call it a focaccia any more, but have reverted to the English equivalent name: hearth bread.
two warnings here: if you're not already an experienced bread baker, this will probably be a bit daunting, as a number of reviewers of the book made clear. second, if you do not own a standing mixer it will be beyond difficult to make. —FermentZed
liquid levain (sourdough starter in which there is a 1:1 proportion of flour and water)
whole rye flour
whole wheat flour
high gluten flour
salt (I use kosher salt; sea salt works well too)
the total weight of flour here will be 600 grams: 75 from the levain, 60 each of rye and whole wheat, 100 of high gluten, and the remaining 305 grams from bread flour.
measure 150 grams of liquid levain to your mixing bowl.
add 605 grams of water to the levain and stir it to make a milky, yeasty liquid. (since the levain had 75 grams of water in it, you now have 680 grams of water.)
add each of the rye flour, whole wheat flour, high gluten flour, bread flour, and salt to the liquid. stir with a wooden spoon or a spatula. cover the bowl and let it sit for about 20 minutes. (this is the autolyse to build up gluten structure.)
set up your mixer with the paddle attachment -- *not* the dough hook -- and begin mixing the dough on a low speed.
after a minute or so, gradually increase the speed of the mixer. I use a Cuisinart mixer which has 12 speeds; I increase it here to a 3. after another 2 or 3 minutes, increase to 6. after another 2 or 3 minutes increase to 9. after another 2 or 3 minutes, increase to 12. stay near the mixer, because 1200 grams of liquid sloshing around at high speed are going to give it wanderlust.
after approximately 20 minutes (sometimes it's been known to take a half hour, sometimes it's been 15 minutes), the dough will have come free of the sides of the mixing bowl and will cohere into a ball on the paddle. slowly reduce the speed until you're back down to 1, and stop the mixer. your ears and neighbors will thank you at this point.
slurp the dough into a rising bowl (I use a 4 liter dough bucket; a mixing bowl with plastic wrap is just fine) and let it rise. I like the flavors that develop during the slow rise of a sourdough, so mine rises for 6 or 7 hours. you can speed up the process by placing your rising bowl in either a larger bowl containing warm water or an oven with just the light turned on.
you will know the dough is completely risen when it is tripled in volume and has large (golf-ball sized) bubbles on the surface. at this point preheat your oven to 475F
line a quarter-sheet pan with parchment paper on the bottom. pour half the olive oil over the paper and spread it evenly. pour the dough into the pan carefully; you don't want to burst the bubbles or deflate it more than necessary. pour the rest of the olive oil onto the dough. when it's slippery with olive oil you will find it's not too difficult to gently stretch the dough to fit the quarter sheet. it doesn't need to get all the way to the edges, because it's now going to rise for an hour while your oven preheats.
time passes, and the dough has risen the second time. sprinkle the top with coarse salt if you like. bake for 20 minutes. if you have a baking stone or steel in your oven, you can release the bread from its pan after 10 minutes and put it right on the stone or steel for the remaining 10 minutes to give it a crisper crust. just baking it in the pan is fine, too.