Remove the skin and all fat from the chicken. In a large pot, add the chicken, tomato, celery, and onion to 6 cups water (about 1.5 liters). Bring to a boil, then skim off any foam or fat that rises to the top.

Peel the carrots and cut them into cubes. Add them to the broth along with the noodles and peas. Once the vegetables are tender, add the zucchini, also diced. Season with salt, chicken bouillon, and a pinch of oregano.

Remove the onion, celery, and tomato from the soup. Beat the egg and add it to each bowl of hot soup, stirring well so the egg cooks in the heat.