Peel the garlic clove and cut into very fine cubes. (Tip: If you only like a hint of garlic, halve the clove and rub the inside of the mortar with the cut surfaces. Then put the rest of the clove to one side).
Process the salt and finely chopped garlic in a mortar to a creamy consistency. It is best to move the pestle in a circular motion inside the mortar.
Gradually add the pine nuts to the mortar in batches and grind.
Now it's the turn of the plucked basil leaves. They are also added to the mortar in small portions, one after the other, while pounding.
Gradually add the grated Parmesan to the mortar and continue to pound. The mixture should have a creamy consistency.
While one hand continues to pound, the other hand slowly pours the olive oil into the mortar in a thin stream. When everything is well combined, the pesto is ready.