Bring a large pot of water to a boil. Meanwhile, finely chop the onion and sauté in a pan with two tablespoons of olive oil. When the onion is brown, add the carrots and zucchini cut into thin strips, season with salt and cook for about 10 minutes on low heat. When the water is boiling, add the salt and drop the pasta without breaking it. In a bowl, combine the eggs, half of the Parmesan cheese and pepper and beat until well blended. When the pasta is done, drain and immediately add to the pan with vegetables, add the beaten eggs and mix until creamy. Add the remaining cheese and pepper and serve hot.