fresh lime juice
- Boil sugar and water in a small saucepan, stirring constantly, until sugar dissolves. Let syrup cool.
- Purée raspberries and syrup in a food processor. Add lime juice. Mixture should be just thick enough to stick to the back of a spoon. If too thick, add a little water.
- Pour into a shallow plastic container or baking dish. Cover and freeze. Stir with a fork approximately every 30 minutes until frozen, about six hours.
- Divide into eight dessert glasses and garnish with lime zest if desired.