Pesto been used for all sorts of cold sauces or dips, mostly without any of the original ingredients: arugula (instead of or in addition to basil), black olives, lemon peel, coriander, or mushrooms. In more northern countries, ramson leaves are sometimes used instead of basil. In the 19th century, Genovese immigrants to Argentina brought pesto recipes with them. A Peruvian variety, known as "tallarines verdes" (meaning "green noodles", from Italian "tagliarini"), is slightly creamier, lacks pine nuts (because of their rarity and prohibitive cost in Peru), may use spinach and vegetable oil (in place of olive oil), and is sometimes served
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