Pour the flour into a large mixing bowl and add the salt and yeast on opposite sides of the bowl. Stir each one in with your finger.
Dump in the sugar, dried rosemary, olive oil, and half of the water. Begin mixing the ingredients together with your hand to form a dough. Gradually add more water you mix until a somewhat sticky dough has formed and all the flour has been picked up from the bottom of the bowl. You may not need all of the water.
Turn the dough onto a floured surface and knead by hand for 20-30 minutes, adding more flour as needed. (This is a longer kneading time than most breads, but is a crucial step.) If you prefer to use a stand mixer, knead with a dough hook on speed 1 or 2 for a shorter time (5-7 minutes).
The dough is done kneading when it meets the following criteria. The dough no longer leaves sticky residue on the work surface or your hands and is tacky to the touch. It should be gloriously smooth and stretchy. When shaped into a taut ball, there should be a couple of air bubbles right under the skin. Most importantly, you should be able to stretch a lump of dough so thin that you can read through it. This means that the gluten is properly developed.
Shape the dough into a ball, place in an oiled bowl, and cover with a clean, hot, damp tea towel. Leave at room temperature until at least doubled in size, about 1 hour.
Lightly smack the top of the proved dough with the back of your hand; it should slowly deflate. Fold the dough over on itself four times, then cover with the same damp towel and let it rise for another 30 minutes.