In a large mixing bowl, combine water and yeast.
Add 1 cup of flour and salt; stir with a wooden spoon until combined.
Stir in rosemary leaves and minced garlic.
Add remaining flour, one cup at a time, stirring until thoroughly combined.
Cover with plastic wrap and set in a warm spot to rise for 1 hour.
Add a tablespoon of olive oil in an 8 or 10-inch cast iron skillet; using a napkin or your fingers, coat bottom and sides of skillet with the olive oil.
Flour your hands; remove plastic wrap and using your hands, transfer dough to prepared skillet and shape into a disk.
Cover with a kitchen towel and let stand for 30 minutes.
Preheat oven to 400 Fahrenheit.
Drizzle remaining olive oil over the top and sprinkle with sea salt.
Score the top of the loaf with some shallow knife cuts.
Bake for 30 to 35 minutes, or until top is nicely browned.
Remove from oven and turn the bread out onto a wire cooling rack.
Leave to cool for a few minutes.