Source: The Martha Stewart Show, February 2010
- 3 cups strained grapefruit juice (from about 3 large grapefruits)
- 1/3 cup superfine sugar
In a bowl, stir together grapefruit juice and sugar until sugar is dissolved. Chill juice, covered, until cold, at least three hours. Freeze in an ice-cream machine, according to manufacturer's instructions, until frozen. Transfer to a covered container and store in the freezer until ready to use, up to 1 week.