Essentially a garlic mayonnaise. Rick Stein also has a separate recipe for allioli, which he describes as a punchy garlic sauce from Spain, but it only differs in not mentioning lemon juice, so the two are probably the same thing.

1. Sprinkle the crushed garlic cloves with salt and then work them with a large knife blade into a smooth paste. Scrape into a bowl.
2. Add the egg yolk and lemon juice. Using an electric hand mixer, whisk everything together and then very gradually whisk in the olive oil to make a thick mayonnaise-like mixture.