Remove the basil leaves from the stems; gently wash the leaves under cold running water; do not fold them as they turn black easily;
Spread the leaves onto a tea towel and dry them. They must be perfectly dry to make pesto;
In a mortar, crush the garlic with some salt;
Add the basil along with all the ingredients except the oil;
Lightly toast the pine nuts in a skillet on the stove top for a few minutes until they turn golden brown (stir constantly); this will make a nuttier taste;
Crush a few leaves of basil, adding only a few leaves at a time with long circular movements of the pestle until there’s a smooth and even paste;
After crushing the basil, add the crushed garlic and pound the mixture until evenly blended. Add the cheese;
and then the oil to bind the sauce and create a creamy paste;
Season with salt.