In a medium bowl, stir together flour, salt and yeast. Add the water and mix thoroughly until you have a wet, sticky dough, about a minute. Cover the bowl with plastic wrap and let sit at room temperature until the surface is dotted with bubbles and the dough has more than doubled in size. This will take at least 12 hours and up to 18.
When the dough has risen, generously dust a work surface with flour. Scrape the dough out of the bowl in one piece. Dust the surface of the dough with flour and, with floured hands, pat and nudge the dough into a 12- to 14-inch square. Brush off any excess flour. Fold the dough in half, then crosswise in half again, into a square 6 to 7 inches on each side.
Place the dough on a floured surface (a countertop or a baking sheet) and place in a warm, draft-free spot. Cover with a clean cloth and let rise a second time for 1 hour. The dough is ready when it has almost doubled. It should hold the impression when gently poked with a finger. If the dough springs back, let it rise another 15 minutes.
Half an hour before the end of the second rise, preheat the oven to 475 degrees. If you have a pizza stone, place it on a rack in the upper third of the oven. Place a cake pan or oven-safe skillet on the bottom rack.
When the dough has risen, place a sheet of parchment paper on a baking sheet. Bring a cup of water to a boil.