Place Seedless Watermelon, raspberries and water in container of electric blender, cover and blend until smooth. Stir in sugar and lemon juice until sugar dissolves.

Pour into a large plastic container and freeze overnight.

Break up the frozen mixture and place in the jug of a large blender with the mint leaves.

Blend until the mixture is a slush-like texture and the mint is evenly distributed. Pour back into the plastic container and freeze overnight again.

To serve, remove the container from the freezer and allow to stand for five minutes at room temperature.

Shave the granita from the block using a strong metal fork and serve in eight glasses topped with a mint sprig.