A classic French vinaigrette was one of the first things my mother taught me to make. We always made a big batch to last the week, and it's a custom I still do to this day. This can be made in any quantity, just remember the 3 part olive oil and 1 part acidic rule. The acidic base can be vinegar or lemon juice or a combination of the two. When we were little I also used to add a touch of honey, but with a good quality olive oil I don't think this is necessary any more, but do add if you prefer.