Crush all ingredients in the blender until a creamy consistency is achieved. Salt the pesto as you like, fill it into small screw-top jars and cover with a thin layer of olive oil.
Close the jars and store in the refrigerator. The pesto will keep in the refrigerator for 2 - 4 weeks.
The amount of olive oil given is approximate, as the leaf mass is often very different and everyone wants the pesto to be more solid or liquid as desired.
Makes 2 small glasses of pesto, keeps in the refrigerator for 2 - 4 weeks.