1. Dissolve yeast in 2 1/2 cups warm water in a large bowl. Weigh or lightly spoon flour into dry measuring cups; level with a knife. Stir salt into yeast mixture. Gradually stir in 7 cups flour, one cup at a time; beat with a mixer at medium speed until dough forms a ball. Turn dough out onto a lightly floured surface; shape dough into a 12-inch log. Divide dough into 3 pieces; shape each piece into a (4-inch) dome-shaped loaf. Place loaves on a baking sheet lightly covered with flour; dust tops lightly with 2 teaspoons flour, and lightly coat with cooking spray. Cover and let rise in a warm place (85°), free from drafts, 1 hour or until doubled in size. (Gently press two fingers into dough. If indentation remains, dough has risen enough.)
2. Position oven rack in lower third of oven. Preheat oven to 350°.
3. Uncover loaves, and brush each with 1 teaspoon oil. Bake at 350° for 30 minutes or until sounds hollow when tapped (bread doesn't brown). Remove from oven; cool on wire racks.