"Whisk 1/2 cup water and the yeast together in the bowl of a mixer. Set aside for 5 minutes until yeast dissolves and turns creamy. Pour 1 3/4 cups warm water into a large measuring cup, add olive oil, and whisk to blend; set aside. Whisk flour and salt together in a large bowl and set aside. Pour water-oil mixture over the yeast and whisk to blend. Add half the flour, and stir with a rubber spatula to mix. Attach dough hook, add remaining flour, and mix on low for 3 minutes or until dough starts to come together. Increase mixer to medium-high and continue to mix for 10 minutes, scraping down hook and sides of bowl as needed, until extremely elastic dough cleans sides of bowl. Transfer dough to a work surface and form into a ball. Place in an oiled bowl, turn it to cover with oil, then cover the bowl tightly with plastic wrap. Allow dough to rise until doubled in bulk, 1 to 1 1/2 hours. Fold dough down on itself to deflate and let rise again until doubled and billowy, 45 minutes to 1 hour.Fold dough over on itself again to deflate and turn it out onto a work surface. Using a metal dough scraper or a knife, cut dough into 3 equal pieces. Shape each piece into a ball, and place each ball in an oiled gallon-size lock-top plastic bag and refrigerate. About 1 1/2 hours before you plan to bake, remove the dough from the refrigerator and take out of oiled bags. Place on a lightly floured surface, dust tops of balls with flour, and cover loosely but completely with plastic. Let rest 1 hour.Position oven rack in lower third of oven and preheat to 450°F. Line two baking sheets with parchment and dust with cornmeal; set baking sheets aside. Fill a spray bottle with water and set aside.Press down gently on each piece of dough, causing bubbles to appear on the sides, then slit the bubbles with a single-edge razor to release the gases. Gently pull and stretch each piece of dough into a 10 inch square. Let the dough relax, covered, for 10 minutes. Transfer foccacias to the baking sheets. Use a single-edge razor to slash each square, cutting a tic-tac-toe pattern. Brush foccacias with olive oil, sprinkle with fresh herbs and coarse sea salt, and put them into heated oven. Bake 15 to 20 minutes, or until they are golden with a heavy speckling of small surface bubbles, spraying the oven with water three times during the first 8 minutes of baking. As soon as you remove the focaccias from the oven, brush them with a little additional olive oil and transfer them to a rack to cool before serving."