Pineapple and Grapefruit Frappé

The Naked Chef Takes Off by Jamie Oliver, 2000, ISBN# 1-4013-0824-4

2 ripe pineapples, peeled and roughly chopped

3 grapefruits, halved and juiced

sugar to taste

Whizz up the pineapple in the blender until smooth and pass through a coarse sieve. Add the grapefruit juice and stir in sugar to taste, remembering that the sweetness from the sugar will lesson slightly when frozen, so use a touch more than you normally would. Place in the freezer for around 2 ½ hours to set, stirring every 45 minutes.