Home › The Waldorf Kitchen › Liaison of Eggs
Liaison of Eggs
Beat up the yolks of the eggs into some of the sauce after cooling it, and then pour this in, stirring slowly. Do not put the eggs in with the hot sauce or they will be sure to curdle.
This is a technique note rather than a dish: how to finish a sauce with egg yolks without scrambling them. The whole thing hinges on temperature control, and the original gives no quantities.
- The hinge: temper, then hold below a simmerWhisk a ladle of hot sauce into the beaten yolks first, then return the mixture to the pan off the direct heat and stir constantly. The finished sauce should thicken between about 160F and 180F; at a boil the yolk proteins tighten and the sauce breaks into grains.
- What Oscar means by "cooling it"Not cold sauce, just sauce dropped from boiling to a temperature the yolks can take without seizing. Taking the pan off the fire for a minute or two is enough.
- Proportions the original omitsRatios vary; something on the order of one to three yolks per cup of sauce, depending on how heavy a nappe is wanted. Yolks are often slackened with a little heavy cream, which dilutes the proteins and makes the liaison more forgiving.
- No boiling afterwardOnce the liaison is in, the sauce cannot be reduced further, reheated hard, or held over a direct flame. Keep it in a bain-marie or serve it at once.
- If it curdlesA lightly broken sauce can sometimes be brought back by immediate blitzing with an immersion blender or by straining through a fine chinois. If it has gone to visible scrambled egg, it is finished.
- Where it belongsThis is the finish for veloutes, blanquettes, fricassees and cream soups, added at the last moment before service, not for tomato-based or heavily acidic sauces, where the acid encourages the yolks to seize.
A liaison is simply the French kitchen word for a binding or thickening agent, covering roux, beurre manie, starch and blood bindings as well as the egg-yolk-and-cream finish. Oscar Tschirky, who ran the dining rooms of the Waldorf, was not a trained chef himself but compiled his book from the working practice of a large French-influenced hotel brigade, which is why short procedural notes like this one sit alongside finished dishes. The technique is far older than the book, belonging to the family of sauces thickened by emulsion and coagulation rather than by flour, and it survives essentially unchanged in blanquette de veau, sauce allemande and the classic cream soups.