To prepare dough, dissolve sugar and yeast in warm water in a large bowl; let stand 5 minutes. Lightly spoon flour into dry measuring cups; level with a knife. Add 2 1/2 cups flour, 1 tablespoon oil, and 1 teaspoon salt; stir well to form a stiff dough. Turn dough out onto a lightly floured surface. Knead until smooth and elastic (about 10 minutes); add enough of the remaining flour, 1 tablespoon at a time, to prevent dough from sticking to hands (the dough will feel tacky.) Place dough in a large bowl coated with cooking spray, turning to coat top. Cover and let rise in a warm place (85º), free from drafts, 45 minutes or until dough is doubled in size. (Gently press two fingers into dough. If indentation remains, the dough has risen enough.)
To prepare sauce, heat 1 tablespoon olive oil in a medium nonstick skillet over medium-high heat. Add garlic, and sauté 1 minute. Add tomatoes; bring to a boil. Reduce heat; simmer 30 minutes or until sauce is thick. Stir in 1/4 teaspoon salt and 1/4 teaspoon black pepper.
Punch the dough down. Cover and let rest 5 minutes. Divide dough into 6 equal portions; working with 1 portion at a time; shape each into a ball (cover remaining dough to prevent drying.) Roll each ball into a 6-inch circle. Place on baking sheets coated with cooking spray. Lightly coat dough with cooking spray; cover with plastic wrap. Let rest 15 minutes.
Cut bell peppers in half lentghwise; discard seeds and membranes. Place pepper halves, skin sides down, on grill rack coated with cooking spray; grill 15 minutes or until blackened. Place in a zip-top plastic bag; seal. Let stand 15 minutes. Peel and cut into strips.
Place dough rounds on grill rack coated with cooking spray; grill 2 minutes or until lightly browned. Turn dough over. Spread 1/3 cup tomato sauce over each dough round, leaving a 1/2-inch border. Sprinkle 1/3 cup tofu and 1/4 cup cheese evenly over each pizza. Divide pepper strips evenly among pizzas. Close grill lid; grill 2 minutes or until cheese melts. Serve immediately.