Rum with lime and mint

A few hours or days before you will drink the cocktail: pour the water with the mint in the blender and blend. Pour into two C’rush trays and freeze.
To prepare the cocktail: wash the limes and cut into quarters. Crush the lime with the sugar in a jug with the help of a mortar. Add the soda and stir well. Add the rum and the C'rushed ice.
Pour into glasses and serve immediately.