Dissolve yeast in warm water in a large bowl; let stand 5 minutes. Lightly spoon flour into dry measuring cups; level with a knife. Add 1 1/2 cups flour, 1 tablespoon cornmeal, oil, and salt to yeast mixture; stir well until smooth (dough will be sticky). Turn dough out onto a lightly floured surface. Knead until smooth and elastic (about 10 minutes); add enough of remaining flour, 1 tablespoon at a time, to prevent dough from sticking to hands.
Place dough in a large bowl coated with cooking spray, turning to coat top. Cover and let rise in a warm place (85°), free from drafts, 1 hour or until doubled in bulk. Punch dough down; cover and let rest for 5 minutes. Roll dough into a 10 x 8-inch rectangle on a lightly floured surface. Place dough on a baking sheet coated with cooking spray and sprinkled with 1 tablespoon cornmeal. Cover and let rise 20 minutes or until puffy.
Preheat oven to 475°.
Sprinkle dough with 3/4 cup mozzarella and 1/4 cup Parmesan cheese, leaving a 1-inch margin around the edges. Combine bell peppers and remaining ingredients; spoon evenly over cheese. Sprinkle 1/4 cup mozzarella and 1/4 cup Parmesan cheese over the bell pepper mixture. Bake at 475° for 18 minutes or until cheese melts.