Pesto where it is known as "pistou". In contrast with "pesto alla genovese", "pistou" is generally made with olive oil, basil and garlic only: while cheese may be added, usually no nuts are included in a traditional "pistou" because no pine trees grow there to provide the nuts. "Pistou" is used in the typical "soupe au pistou", a hearty vegetable soup with "pistou" flavour. The sauce did not originally contain basil, however; instead, cheese and olive oil were the main constituents. Sometimes almonds are used instead of pine nuts, and sometimes mint leaves are mixed in with the basil leaves. It
Pesto by crushing garlic, salt, cheese, herbs, olive oil and vinegar together. The use of this paste in the Roman cuisine is mentioned in the "Appendix Vergiliana", an ancient collection of poems where the author dwells on the details about the preparation of "moretum". During the Middle Ages, a popular sauce in the Genoan cuisine was "agliata", which was basically a mash of garlic and walnuts, as garlic was a staple in the nutrition of Ligurians, especially for the seafarers. The introduction of basil, the main ingredient of modern pesto, occurred in more recent times and is first documented only in