20 minutes, plus freezing time
6 egg yolks
1/2 cup sugar
1/2 cup sweet Marsala, or another desired liquor or liqueur
1 pint cold heavy cream, whipped to medium peaks in a large bowl
1. In a large bowl,
whisk together the egg yolks and sugar until combined and frothy. Whisk in the Marsala.
2. Set the bowl
over a large pot of simmering water, making sure the bottom of the bowl does not touch the water. Continue to whisk until the mixture increases in volume and thickens to a thick, foamy cream, easily coating the back of a spoon. The consistency should be similar to that of a very thick hollandaise.
3. Remove from heat
and gently fold the zabaglione into the whipped cream. Place the mixture in a baking dish or bowl and cover the surface with a sheet of plastic wrap. Freeze until firm, about 1 ½ to 2 hours. This makes a generous quart of frozen zabaglione.