In the bowl of your stand mixer or a large mixing bowl, add the flour, yeast, salt, sugar, warm water and two tablespoons of olive oil. Stir with a spoon to combine.
Knead the dough with a machine using dough hooks for four minutes, or knead it by hand on a clean, floured surface for six minutes. If your dough is sticky and not coming together into a ball as you knead it, add 2 extra tablespoons of flour as needed. The dough should be smooth and not sticky.
Grease the mixing bowl with cooking spray (no need to clean it first). Place the ball of dough in the bowl and roll the dough around to coat it with oil. Cover the bowl tightly with plastic wrap. Let the dough rise at room temperature for one hour or until doubled (I place mine inside the microwave, which is turned off.)
Brush two tablespoons of olive oil on the bottom of a 9x13 metal pan or a half-sheet pan with sides. Punch down the risen dough. Shape it into a 9x13 rectangle. It helps to grasp the dough by the edges, hold it up, and let it stretch out. Rotate the dough a bit and continue, pressing the dough with your fingers in the thick spots to thin it out. Press the dough into your pan.
Cover the pan with plastic wrap and let the focaccia dough rise for 20 minutes at room temperature.
When the dough has 15 minutes left to rise, preheat your oven to 425 degrees F. Peel and slice the garlic. If using fresh rosemary, rinse the spring and pat it dry. Pluck off the rosemary needles from the stem. Grate the Parmesan if using fresh cheese.
After the second rise is finished, use your fingertips to make deep dimples all over the focaccia dough.
Pour two tablespoons of olive oil over evenly over the dough. Let it pool in the dimples. Place a slice of garlic in each dimple (or sprinkle on garlic powder). Sprinkle rosemary, Parmesan and black pepper over the top of the focaccia.
Bake the Parmesan focaccia for 20-25 minutes, or until the surface is browned.
Remove the focaccia from the oven and set the pan on your stovetop. Slide two large spatulas under the bread to transfer it to a cooling rack (or invert the focaccia onto a clean baking sheet, then invert it onto the cooling rack.) Let the focaccia cool for 10-15 minutes. Lightly sprinkle on sea salt. To serve, transfer the focaccia to a cutting board and cut into slices. Serve with olive oil for dipping.
It's best to freeze leftover sliced focaccia in a zip-top bag to keep it fresh. Otherwise, wrap the focaccia in plastic and store it at room temperature for 2-3 days. Reheat focaccia in the microwave for a softer texture or use a toaster oven or regular oven to crisp it.
Notes
When making breads from scratch, the temperature and humidity of your kitchen will affect the dough. If the dough is sticky and not coming together, it needs more flour. Add a couple of extra tablespoons of flour until the dough comes together.Make Sure Yeast is Fresh - If using instant yeast from a jar, instead of looking at the expiration date, consider when you first opened the jar. If it's been more than four months since you opened it, the yeast won't work as well, and the dough won't rise properly.For Active Dry YeastIf using active dry yeast, you'll need to proof it first. Stir the 1 ¼ cups of warm water and 1 teaspoon of sugar together in a measuring cup. Sprinkle the yeast on top, stir and wait 10 minutes.If the mixture bubbles, the yeast is good. Add this mixture to the mixing bowl with the flour, salt and olive oil. Stir to combine and proceed with the recipe.If the active yeast doesn't bubble after 10 minutes, it will not work. Discard it and use fresh yeast.Rising Time of DoughThis recipe calls for a first rise of an hour, and a second rise of 20 minutes. It produces nice results, but if you want extra airy focaccia, you can refrigerate the ball of dough overnight for the first rise.To Freeze Focaccia DoughYou can freeze focaccia dough and use it within three months, for best quality. Coat the dough lightly in olive oil to prevent drying, then wrap it in plastic. Place the wrapped ball of dough in a zip-top freezer bag.To thaw the dough, refrigerate it overnight before using it.