1. Plunge the carrots into a large pot of boiling, salted water and cook until soft, about 5 to 7 minutes. Remove to a large mixing bowl with a slotted spoon. Repeat this procedure with the green beans, the squash, and the peas, bringing the water back to a full boil each time. Set the cooked vegetables aside. Alternatively, follow manufacturer's instructions for cooking vegetables in the microwave oven.

2. In a large sauté pan, heat the oil over moderate heat. Add the garlic, the onions, and the red peppers. Cook over moderately low heat until very soft, about 15 minutes. Drain any water that has accumulated from the cooked vegetables and add to the sauté pan.

3. In a large amount of boiling, salted water cook the pasta until tender, about 7 to 10 minutes. Heat the vegetables in the sauté pan over moderately high heat, stirring frequently. Season with salt and black pepper to taste. In a large mixing bowl, toss the pasta, the basil, and the vegetables to mix well. Serve immediately with Parmesan cheese if desired.