Clean carefully the basil leaves. Put the basil in a blender or food processor at medium/low speed with the garlic cloves; add pine nuts (almonds/nuts) and a pinch of salt.
Start grinding until it becomes a paste.
Next incorporate the olive oil little by little until a uniform mix is obtained. The ideal consistency is not very liquid nor a solid green and undetermined mass.
Add the parmesan cheese and stir. Taste the salt, and adjust to your preference. Likewise, if you think that it should be more liquid a little more oil may be added. Store the mix in a glass jar. Close tight and refrigerate.