"Fiorentina Style" Onion Soup

Onion soup has been present in Tuscan recipe books since 1500, and represents a cornerstone of regional gastronomic tradition, in particular that of Florence. The onions are cooked together with the celery, carrots and peas, with the addition of high quality salt, pepper and extra virgin olive oil. To enjoy this soup at its best, heat it up and serve it with slightly toasted slices of bread.