Although mayonnaise dressing is prepared without the application of heat, it is not one of the simplest dressings to prepare. It meets with much favor, being used almost as extensively as French dressing, but it is perhaps less desirable with fruit salads than with others. It is also much used as a basis for numerous other dressings. Since it requires considerable time for its preparation, a wise plan is to make more than enough for one meal. However, it should not be made in large quantities, for the oil separates from the remainder of the ingredients if it is allowed to stand too long. If it is thoroughly beaten and kept extremely cold, it may perhaps keep for a week, but keeping it longer than that is not advisable. Before serving, it may be thinned by beating either sweet or sour cream into it. It may be made fluffy and light and its quantity may be increased by beating whipped cream into it.
Mix the dry ingredients in a bowl. Separate the eggs and add the yolks to the dry ingredients. Beat these with a rotary egg beater until they are well mixed. To this mixture, add a few drops of oil and continue to beat. Add a drop of the vinegar or lemon juice, a few more drops of oil, and beat constantly. Gradually increase the quantity of oil added each time, but do not do this rapidly. As the oil is added and the beating is continued, it will be noted that the mixture grows thicker, but when vinegar is added the mixture is thinned. The quantity of vinegar is so much less than that of oil that the oil may be added in small amounts two or three times in succession before vinegar is added.
This process is rather long and slow, but if the mixing is done correctly, the result will be a thick, smooth mixture that will not separate for possibly 6 or 7 days. Mayonnaise mixers, which may be procured for making this dressing, make the work easier, but they are not at all necessary. Mayonnaise may be made as successfully with a bowl and a rotary beater, if it will just be remembered that the liquid ingredients must be added slowly and that they must be as cold as possible.