Marinate the sultanas in the Vin Santo for at least 1 hour.
Put the lobsters in boiling salted water and boil for 3 minutes. Turn the heat off and leave to stand for 5 minutes. Remove the lobsters from the water, cut in half and remove the stomach and sandbag. Crack the claws.
Melt the butter in a pan and add a small pinch of nutmeg,
Vin Santo is made from white grapes which are hung on racks during the winter. They shrivel and concentrate their sugar, and are then pressed during Easter Holy Week–hence its name.