Mix the oil and seasoning. Add the vinegar gradually, stirring constantly with a wooden spoon so that an emulsion is formed.
Where suitable, orange or grapefruit juice may also be used.
A graduated medicine bottle is most useful for making French dressing. The oil and vinegar can be measured accurately without waste, and the dressing vigorously shaken to mix it. It can be stored in the larder or refrigerator, the bottle being well shaken before the dressing is used.