Cook zucchini in boiling salted water in a saucepan for 5 minutes, or until just tender-crisp. Drain, immerse in cold water to retard cooking process and then drain again. In a bowl, combine zucchini with the salad dressing. Marinate in refrigerator for 3 hours or longer. At least 30 minutes before serving, in a separate bowl, gently combine the cheese, onion, green chile peppers, red pepper, avocado, and cilantro. Chill for 30 minutes. Serve on a bed of greens. Top with freshly ground pepper and, if desired, the tomatoes, sunflower seeds or nuts.