Heat a medium frying pan and grease with olive oil. Add eggs and make sure the frying pan is covered with the egg mixture. Swirl the pan with your hand to ensure eggs cover entire pan. Place vegetables on omelet and let cook until set for 4-5 minutes. Cover with a lid and let cook for another 3 minutes to be sure vegetables are softened. Slide omelet onto plate, sprinkle with parmesan cheese and enjoy!