Wash and cut the zucchinis into thin slices. Cut the tomato into cubes. Wash the peppers, cut them in half, remove the seeds and cut the onion into slices. Put all the vegetables in a pan with a little water and salt and cook enough to get crispy. Add the oil and parsley and set aside. Meanwhile, cook the pasta in plenty of boiling water and salt, until cooked through. Drain, mix with the vegetables and serve.