1 large (2 1/2- to 3-lb) firm-ripe papaya (preferably Caribbean or Mexican), peeled, seeded, and coarsely chopped (2 cups)
5 to 8 tablespoons vanilla granulated sugar (see cooks' note, below)
2 to 3 tablespoons fresh lime juice
1 1/4 cups chilled heavy cream

Mash papaya flesh with a fork until smooth or pulse in a food processor until coarsely pur ed. Add 5 tablespoons sugar and 2 tablespoons lime juice and stir or pulse to combine. Add more sugar and lime juice to taste (papayas vary in sweetness and acidity).

Beat cream in a large bowl until it holds soft peaks, then fold in papaya mixture gently but thoroughly.

Divide among 8 (6-ounce) glasses and chill at least 1 hour to allow flavors to develop.

Cooks' note:
To make vanilla granulated sugar, combine sugar and 1 vanilla bean, halved lengthwise and chopped, in an airtight container and let stand, covered, at least 24 hours. Sift before using.

Makes 8 servings.