Zabaglioni is an Italian dessert, or sometimes a beverage made with egg yolks and a sweet wine. Some versions incorporate spirits such as cognac.
4 egg yolks
4 tbspns caster sugar
4 broken half-eggshell measures of dry Marsala wine
Place the egg yolks and sugar in a glass bowl and whisk in one direction until a paste forms. Add half the wine and whisk again until you have a thick, smooth custard with just a few bubbles.
Place the bowl over a pan of simmering water - the water must not actually touch the bowl - and carry on whisking while gradually adding the remaining wine.
This can take 10 minutes or more. The idea is to thicken the mixture with air and to warm it, so you may have to take the bowl off the heat every now and then to avoid cooking it through. The result should be a silky cream that is almost as thick as mayonnaise. The test for readiness is that a spoon will stand upright in it when poured into a glass.
You can experiment with presentation. I have used fresh fruit and mint, but you can use grated chocolate, a tuille, fruit purée, etc.