Aioli is a cold emulsified sauce made of garlic and olive oil. Normally egg is also added for ease of mixing. There are many variations, such as the addition of mustard. In France, aioli is traditionally served with seafood, fish soup, and croutons and is usually served at room temperature. The name aioli (alholi) comes from Provençal "alh" garlic and "oli" oil.

Puree garlic in a food processor or blender. Whisk the egg yolks in a small bowl until light and smooth, and add to the garlic. Add salt and pepper to taste, lemon juice, and mustard, and process to a smooth paste. With the machine still running, add the oil, very slowly, into the mixture in a constant, steady stream, blending constantly. Continue the blending until you obtain a thick, shiny, firm sauce. Transfer to a storage container, cover with plastic wrap, and refrigerate until ready to use.

Learn more about aioli: In Provence, aioli also designates a complete dish consisting of various boiled vegetables usually made of carrots, potatoes, and green beans, boiled fish, desalted salt cod or monkfish, and boiled eggs served with the aioli sauce.

The garlic is often ground with salt in a mortar and pestle to lead to a smooth aioli. Egg yolks, garlic and Dijon mustard if adding this as a common variation on the basic aioli, are combined first with a whisk, and the oil is added slowly with whisking and the lemon juice is added slowly with whisking to create the emulsion. The additions of the dissimilar ingredients must be slow to start and then can be faster once the initial emulsion has formed.

Aioli has become popular as an accompaniment in Australia, often served alongside French fries.