Salsa allioli

Preparation:
Pound the garlic to a paste, together with a little salt, in a mortar.
Add the olive oil, drop by drop, and keep stirring with the pestle, in the same direction, until you have a thick, dense sauce.

Variations:
You can add an egg yolk before adding the oil.
You can also make the "allioli" in a food processor or with a hand-held blender.