1 part cider vinegar
3 parts olive oil
freshly grated garlic (or jarred garlic in olive oil)
I grate a small clove, add small amounts of olive oil and vinegar, stir it up with the little brush and use the brush to pour it off the plate onto two dinner side salads or one large salad.
If I used as much garlic as below, I'd better be making at least a cup of dressing (1/4 cup vinegar, 3/4 cup oil). If I am making that much, I whisk it together in a small bowl. With extra virgin olive oil it turns a lovely greenish yellow.
I have a small grater that looks like this:
Started 9th of April 2007; Started IP protocol 20th September, 2012 at 193 pounds.
Reached goal March 2013; Maintained via Paleo/Primal since.