Zabaglione

INGREDIENTS
4 egg yolks
4 tbsp caster sugar
8 tbsp Marsala
finely grated zest of 1 orange
8 sponge fingers or biscotti, to serve

METHOD
Bring a large saucepan of water to the boil, then lower the heat to simmer.
Put the egg yolks, sugar, Marsala, and half the orange zest into a large glass or china bowl and place on top of the pan of simmering water. Start to whisk immediately, using a balloon whisk.
Keep whisking for 5–10 minutes, or until the mixture is pale, thick, fluffy, and warmed through.
Pour into 4 cocktail glasses and decorate with the remaining orange zest; serve immediately with sponge fingers or biscotti.