Add the water, yeast and sugar to the bowl of a mixer and mix with a fork to combine. Set aside for 5-10 minutes, until the yeast is nice and frothy.
Add the salt and 4 cups of the flour to the bowl. Mix on low to medium-low speed with the paddle attachment until combined. It will be pretty wet at this point. Add the remaining cup of flour ¼ cup at a time until the dough is soft and pliable, but not sticky.
Turn the dough out onto a floured surface and knead for 3-4 minutes by hand until smooth. Pour the olive oil into a large bowl and add the dough, turning to coat the entire thing with the oil. Cover with plastic wrap or a clean kitchen towel.
Let the dough rise until doubled, about an hour at room temperature. You can speed up this process by setting the oven to warm or the lowest heat, typically 170℉. Place the covered bowl in the oven and drop a couple ice cubes on the bottom of the oven to create moisture. Check the dough after 20-25 minutes.
Once doubled, split the dough into two equal portions. Roll each half into a rectangle about 9x15 inches, though it doesn’t have to be exact. Roll the dough up the long side and pinch along the seam and ends.
Place the two rolls of dough on a large parchment lined baking sheet. Use a sharp knife to cut 4-5 slightly diagonal slashes across the tops of the dough. Cover with a kitchen towel and let rise for 20-30 minutes.
While the loaves rise, preheat the oven to 400℉. When the loaves have nearly doubled in size, bake on the center rack of the oven for 18-22 minutes. If you want to create steam to add to the crispiness of the crust, toss a few ice cubes on the bottom of the oven and close the door quickly to trap it inside.
If desired, brush the outside of the loaves with melted butter just after they come out of the oven.
Allow to cool completely before slicing to avoid the bread turning gummy.