300g (10½oz) ripe (but on no account overripe) William pears
80g (3oz) caster or icing sugar
Peel the pears, cut them into quarters and core them. Rub the pieces of pear all over with half a lemon to keep them white.
Put the quartered pears in a small saucepan with the sugar and just cover with cold water. Poach gently at a slow simmer for 10–15 minutes.
Take out the pears and reduce the cooking liquid by boiling until it starts to thicken and become syrupy, without letting it brown. Allow pears and syrup to get quite cold, then add the juice of a lemon. Purée everything together in the liquidiser or through the fine blade of the mouli-légumes. Transfer the mixture to the ice-cream maker and freeze. To serve, scoop the sorbet into balls with a tablespoon dipped in hot water and serve in well-chilled ice-cream dishes.