A basic vinaigrette is made of oil, an acid such as vinegar or lemon juice, salt, and pepper. Some variations may also include additional ingredients such as mustard, garlic, honey, or herbs to add flavor. The ingredients are typically mixed together in a ratio of 3 parts oil to 1 part acid. In this Meyer lemon oregano vinaigrette, we have closer to a 2 part oil to 1 part acid ratio. This is because of the relatively low acidity of Meyer lemons, compared with regular lemons or vinegars.