Make a water bath by bringing water to a boil.
In a heatproof bowl, mix all the ingredients for the zabaglione.
Put in in the simmering water and whisk constantly until you get an airy consistency. Make sure the sauce does not get too hot. If it exceeds 185 degrees – the zabaglione will go lumpy and look like scrambled eggs.
Remove the bowl from the water bath and continue whisking until it cools off.
Divide the berries evenly between 4 bowls and pour some zabaglione on each. Serve.