Cook pasta as package directs. While the pasta is cooking, heat the oil in a large skillet and sauté the garlic and onion for 4 to 5 minutes. Add the crushed red pepper, salt, spinach and tomatoes. Sauté 1 to 2 minutes. Add the tomato cooking liquid. Drain the pasta and add to the skillet. Season with black pepper and add extra salt if desired. Toss the pasta and vegetables until heated through. Place in serving bowls.
Per serving - 270 calories, 7 g fat (23% calories from fat), 9 g protein, 43 g carbohydrate, 5 g fiber, 0 mg cholesterol, 87 mg sodium