Put the egg yolk in a bowl and season lightly. Add the oil to the egg in the initial stages with a very sparing hand, literally drop by drop, and beating in each addition of oil before adding the next. Once the mixture starts to thicken, the oil can be added more liberally, but no more than a thin stream, about a tablespoon at a time. This too should be beaten until the mixture looks thick and glossy, but with no surface film of oil, before you add the next stream of oil. When all the oil has ben taken up, add more seasoning to taste, the lemon juice or vinegar, or add an extra flavouring. If the mayonnaise sems very stiff and oily-looking, you can beat in a tablespoon of boiling water, which will emulsify and give a smooth, velvety texture.
Mustard, chopped herbs, horseradish, tomato purée, chopped cornichons and spring onions are just some of the many ingredients you can use to flavour mayonnaise. Seville orange juice can be used to sharpen it, as can the juice of a blood orange, when it becomes mayonnaise maltaise. To make mayonnaise mousseline, which is the classic accompaniment to asparagus, season the mayonnaise with tarragon vinegar, and fold in whipped cream. To make a lighter version, I often simply fold in a stiffly beaten egg white. Sauce maltaise and sauce mousseline are made in the same way, but with a base of hollandaise sauce, not mayonnaise.
© 2000 Frances Bissell. All rights reserved.