This is a lovely, slightly sharp sherbet with a clean, pure taste. In my mind, the definition of a sherbet is a sorbet with just the smallest amount of cream added or, in this case, crème fraîche. Leave out the cream if you prefer. The flavour will be just that much more immediate.
1kg plums (we use Opus, but Victoria plums are delicious too)
220g caster sugar
a pinch of salt
50ml crème fraîche
Place plums, water and sugar into a heavy-based pan over a medium heat and bring to a simmer for 8-10 minutes, or until plums are soft and falling apart. Remove pan from heat and pass plums through a chinois (a fine mesh strainer). Press down firmly on the purée to push some of the flesh through, giving the sherbet a lovely rich body.
Place the crème fraîche in a bowl and pour the strained purée over it, stirring as you do so. It is important to add the purée to the crème fraîche and not the other way round to ensure an even and smooth purée.
Add the salt (this helps to bring out the flavour of the plums). Allow to completely cool , before pouring into an ice-cream maker (follow the manufacturer's instructions).
If you don't have an ice-cream maker you could do without the cream and pour the purée into a shallow tray and place in freezer. After 45 minutes, drag a fork through the fruit, drawing in from the sides. Return to freezer and repeat this process twice more at half-hour intervals.