Prep
In the bowl of a stand mixer fitted with the dough hook attachment, or in a large bowl, combine all the ingredients. Mix on the lowest speed for one minute, or by hand until well combined. The dough will be sticky. Let it rest for 5 minutes.
With the mixer on medium speed, mix for 3 minutes, or continue mixing by hand. The dough will still be sticky.
Spread a drizzle of olive oil on your work surface, and rub a spatula with oil(to keep the dough from sticking). With the oiled spatula, scrape the dough out onto your work space and rub your hands in the oil. Stretch and fold the dough once from each direction.
STRETCH AND FOLD: reach your hands under front end of the dough, stretching it out towards you, and folding it back onto the top of the dough. Repeat from the back of the dough, pulling it outwards, and folding back onto the top. Repeat from each side, oiling your hands as needed to prevent sticking.
Flip the dough over and tuck it into a ball.
Place the dough into a ziplock bag bag misted with spray oil(or rubbed with regular oil)/or a covered bowl. Seal the bag and leave it on the counter to rise(for same day baking), place in the fridge for overnight fermentation(recommended), or freeze, depending on when you want to bake.
FREEZE: freeze the dough immediately after forming it into a ball(for up to a month) and transfer the dough to the fridge the day before you want to bake, then continue on with instructions for NEXT DAY BAKING.
SAME DAY: If you want to bake the focaccia the same day, leave it on the counter, covered, for a minimum of 2-3 hours before baking (up to 4 hours).
NEXT DAY or up to 3 DAYS LATER(recommended): 90 minutes before you plan to bake, remove the dough from the fridge. Cut the dough into desired amount of pieces(2 for regular round focaccias or see following recipe requirements). Round each piece into a ball and place on a baking tray fitted with a parchment sheet, cover it, and let the dough rest until baking time.
Preheat the oven and baking stone(or a baking sheet turned upside down) to the hottest setting.