Mix the flour, yeast, and sugar. Add the water and oil (reserve some of the oil for the finish).
Add the salt, and finally add the little bit of reserved oil.
Knead a further 10 minutes, until your dough is soft, pliant, and pleasant to the touch.
Form a ball of dough and put it into a bowl. Cover with Saran wrap pressed to the dough, and add an extra cover.
Allow to rise for an hour.
Divide the dough into your desired Focaccia size. (To create a symmetric Focaccia loaf, use a round cutter). Roll the dough with a rolling pin, and finish the shape by gently pressing it with your fingers. Aim for thicker margins around the edge than in the center.
You can vary your Focaccia toppings: scatter the top with multi-colored peppers, sliced tomatoes, red or white onion rings, sweet potatoes or fried eggplant, cheese, and olives. (You can also try sprinkling the dough with sage and coarse salt for a more sophisticated flavor).
Finally, drizzle olive oil over the top – including the margins.
Bake for 15 minutes.