A classic Sgroppino is made with lemon sorbet and vodka, topped with sparkling wine. We've gone for a Bellini-style twist with a nectarine sorbet. The sorbet can be made ahead and ready to go when it's time to start the festivities. It's quite forgiving when it comes to the choice of wine; it could be prosecco, say, a light Lambrusco or Franciacorta for something a little special. This Sgroppino could also be served in place of dessert, perhaps using moscato d'Asti as the sparkling. For extra punch, add a touch of vodka or peach liqueur.