Cut the strawberries into circles or quarters. I leave some of it, and some of it will be used to make the syrup.
Half of the strawberries are transferred to a ladle, pour a little water, add sugar and bring to a boil. Simmer the syrup for 10 minutes. I grind the berries with a blender to a puree-like state and cool the syrup.
I put the remaining strawberries and Basil sprigs in the container.
I add the juice of one lemon, rum, chilled syrup and sparkling water.
I'm cooling a cocktail in the refrigerator. Before serving, add ice cubes.