Salsa Aïoli - Recipe

Combine the egg yolk and the garlic in a bowl, and season them with salt and pepper. Add the oil a few drops at a time, stirring briskly with a whip, and when the sauce reaches the consistency of mayonnaise, stir in lemon juice to taste, then the remaining oil. Check seasoning and it's ready.

A note: Since the sauce is emulsified, like mayonnaise, it may behave like mayonnaise, and refuse to set well if there's a thunderstorm brewing when you make it.

A Quick Answer to Cosetteworld:

I confess I am not an expert on Aioli. However, Antonio Piccinardi doesn't discuss it in his Dizionario della Gastronomia Italiana. The folks at La Cucina Italiana do (quickly) in their Grande Dizionario Enciclopedico, saying it's from Provence, while a number of other Italian sources I checked say it's actually Catalonian in origin, and spread from thence to Mediterranean France, and on to Liguria. All of the modern Italian (in Italian) recipes I have seen include egg.

Kyle Phillips, Your Guide to Italian Cooking