Preparation In a blender, combine the grapefruit juice and sugar, and blend until the sugar is dissolved. Add the Campari, pour the mixture into the container of an ice cream machine, and churn according to the manufacturer's instructions. Transfer to an airtight container and freeze for at least 2 hours before serving. Reprinted from the book THE CIAO BELLA BOOK OF GELATO AND SORBETTO by F.W. PEARCE & DANILO ZECCHIN. Copyright © 2010 by F.W. PEARCE & DANILO ZECCHIN. Photographs copyright © 2010 by IAIN BAGWELL. Published by Clarkson Potter, a division of Random House, Inc.