In a large bowl, mix together flour, salt, and instant yeast.
Add warm water and olive oil. Stir until a sticky dough forms.
Cover for 15 minutes and do one stretch and fold. Let the dough rest for another 15 minutes and repeat stretch and fold.
Add olive oil to a 9x13-inch baking pan and spread it around the bottom and sides.
Transfer dough to the pan and gently stretch it toward the edges. Let rest if needed, then stretch again.
Cover and let rise for 1 hour or more, until puffy.
Preheat oven to 400°F.
Drizzle dough with olive oil. Use your fingers to make dimples all over the top.
Sprinkle with flaky salt, rosemary, and garlic if using.
Bake for 22 to 28 minutes, or until golden brown.
Cool slightly, slice, and serve.
