This basic aioli recipe has the makings of a good mayo flavored with garlic—which is popular culture's definition of aioli anyway.
Aioli is a sauce made by emulsifying olive oil into mashed garlic. But nowadays, the term refers to any garlic-flavored mayo. Google "aioli," and it brings up a dictionary entry describing it as "mayonnaise seasoned with garlic." More-so, people even extend the term to mean any flavored mayo.
This basic aioli recipe follows the garlic mayo definition. So its method is similar to making homemade mayonnaise. It's an emulsion, a mixture of two liquids that don't normally go together; in this case, it's oil and egg yolks. Basic mayo recipes use the same two base ingredients, plus acid to help it emulsify better and salt for seasoning. The only difference here is that we add garlic, essentially transforming it into an aioli.
Beat the egg yolk, garlic, and lemon juice or vinegar until frothy and peak forms at the top.
Gradually add the oil while constantly whisking until it begins to stiffen. Add water to thin out the mixture, if necessary.
Season with salt while giving it one last whisk.
Store in a sealed container in the fridge. Serve within the next 3 days.
