Focaccia: Schiacciata Con Biga (with starter)

Dough:

  3/4 teaspoons active dry yeast
  1¼ cups + 2 tablespoons warm water (105 to 112°F)
  100 grams starter (bit more than a big ice cream scoop)
  2½ tablespoons olive oil
  500 grams unbleached all-purpose flour (3½-4 cups)
  1½ teaspoons sea salt
  2 tablespoons olive oil
  3/4 to 1 teaspoon fleur de sel (premium sea salt)
  
Measure out the warm water, put in the KitchenAid mixer bowl, and measure the 
temperature (105-115°). Whisk in the yeast and let stand 10 minutes. Add the 
olive oil. Break up the (room temperature) starter into little bits and add. 
Stir briefly with paddle attachment until the mixture is chalky white. Add the 
flour and salt and mix 2 minutes on low speed or until a dough forms, then 
change to the dough hook and knead 5 minutes on low speed. The dough should be 
velvety and moist but not sticky.

First rise: place the dough in an oiled bowl, cover tightly with plastic 
wrap, put in a 75-78° environment, and let rise until doubled, 1½ to 3 hours.

Shaping and second rise: Oil a cookie sheet and press the dough out to a
12" square. Cover with a towel and let rise until doubled, 2-4 hours.

Third rise: Dimple the dough with fingertips and correct any misshaping.
Brush with oil and sprinkle on the salt and then let it sit 30-45 minutes
while you preheat the oven to 425°F.

Baking: sprinkle a little more oil over the top. Bake until golden brown on 
top and bottom, 25-30 minutes.

Biga (focaccia starter)

½ teaspoon active dry yeast
¼ cup warm water (105° to 115°F)
1¼ cups plus 2 tablespoons water, room temperature
3¾ cups (500 grams) unbleached all-purpose flour

Sprinkle the yeast over the warm water in a large mixing bowl, whisk it in 
and let stand until creamy, about 10 minutes. Stir in the remaining water 
and then the flour, mixing with a wooden spoon for about 100 strokes or 
with the paddle attachment of a heavy-duty mixer until a sticky dough is formed.

Rising: Leave the dough in the mixing bowl or transfer it to an oiled bowl. 
Cover it tightly with plastic wrap and let it rise at cool room temperature 
for 6 to 24 hours. The starter will triple in volume and then collapse upon 
itself. It will still be bubbly, wet and sticky when ready to use. Cover and 
refrigerate after 24 hours. When needed, scoop out the desired amount.

I take a large ice cream scoop and a muffin tin and put a scoop of starter 
into each muffin indent, then freeze the muffin tin. When frozen, I pop out 
the frozen pucks of starter, each close to the amount needed for the recipe 
above, and put several pucks into a quart Ziploc bag, seal it, and put it 
back in the freezer until needed. I use one puck per recipe above.