What you need is a mortar, a lot of patience, and a little bit of strenght!
I’m not good with quantity but that’s my way:
- fill the mortar with packed basil leaves (dry).
- Add 1 garlic
- Add some salt
Start working with the mortar untill the basil and the garlic are perfectly chopped and melted together.
At this point add the some pine nuts (pinoli) and keep working with the mortar.
When the pine nuts are melted with the pesto add oil, parmigiano and pecorino cheese.
Fix the flavor with salt and pepper.
To get an idea of the ingredients proportions have a look at this recipe