Pesto

Pesto (meaning Paste) is a type of sauce that originated in the Italian region of Liguria. The uncooked sauce is made of basil which is crushed. Other ingredients are garlic, salt, pine nuts, olive oil, and certain types of cheese (most often Parmesan cheese, Pecorino Sardo or Pecorino Romano). 
Pesto is often used as a sauce for pasta.
There is a similar dish in the Provence, in France. It contains no nuts or cheese. It is called Pistou.