Preparing the raspberry base
In the bowl of a food processor, combine the berries, the preserves, and the lemon juice and process to a puree. Strain the puree to remove the seed, using a wooden spoon to tap the edge of the strainer and encourage the puree through. Pour the mixture into a shallow metal pan.
Step 1: Preparing the raspberry base
- ¾ pound fresh raspberries or 1 (12-ounce) package unsweetened frozen raspberries, thawed
- 1 cup raspberry preserves
- 1 tablespoon freshly squeezed lemon juice
Step 2: Freezing and processing
Freeze until solid around the edges but still just a little soft in the center, stirring every hour until the mixture has the texture of a soft-serve ice cream, about 2 ½ hours.
Transfer the frozen puree to a bowl of a food processor and process until light, fluffy and smooth, about 20 seconds. Return the lightened puree to the metal pan and return it to the freezer for another 2 ½ to 3 hours. Alternatively, at this point, to make ahead, the mixture can be completely frozen and then softened by moving to the refrigerator for about an hour before serving.
Step 3: Serving
- 4 mint sprigs, for garnish
- Additional raspberries, for garnish, optional
To serve, scoop the granita into glasses or dishes and add a sprig of mint and fresh raspberries. Serve immediately.