The secret to holding sabayon (zabaglione) is to keep whisking it over ice without stopping until it is quite cold.
Put two trays of ice in a container large enough to just hold a wide, rather shallow, stainless-steel mixing bowl. Half fill the container with water and keep this ice bath by the stove. Boil a pot of water that is large enough to hold the cooking bowl so that it sits half down into the pot.
Combine the yolks, sugar, and salt in a stainless-steel mixing bowl. Mix well and add the champagne or wine.
Over barely simmering water, whisk the mixture vigorously until it is thick and pale yellow, about 10 minutes. Put the cooking bowl immediately into the ice bath and whisk vigorously again until the sabayon is cold. Keep chilled. When you want to use the sauce, whip the cream and fold it into the sabayon.
© 1986 Jeremiah Tower. All rights reserved.