Garlic pounded with salt and beaten with olive oil into a thick, pungent emulsion.
What makes it aïoli
A lot of raw garlic — it should be strong.
Olive oil, beaten in drop by drop.
Made in a mortar, not a blender, if you can.
Where it comes from
The name is simply garlic and oil in Provençal. Purists make it with those alone, pounded in a mortar; most cooks add an egg yolk, which makes it far more forgiving.
It gives its name to a meal, too: le grand aïoli, a spread of poached salt cod, boiled vegetables and eggs around a bowl of it, traditionally eaten on Fridays and at village feasts.
How it varies
Le grand aïoli
The feast: salt cod, snails, eggs and boiled vegetables with the sauce.
Rouille
With chilli or saffron and bread, the rusty sauce for bouillabaisse.