Lemonade granita

Ingredients

175g/6oz caster sugar
6 lemons, juice and grated rind
1 lemon grass stalk, roughly flattened with a rolling pin
450ml/¾ pint soda water

Method

1. Place the sugar, lemon rind and juice, lemongrass stalk in a pan with 150ml/¼ pint water.
2. Heat gently, stirring until the sugar dissolves then simmer gently for five minutes then allow to cool.
3. Strain the liquid into a rigid container then stir in the soda water.
4. Transfer to the freezer for at least two hours, whisking every 20 minutes to stop crystals forming.
5. Serve in glasses.