Wash the basil and then dry it. Put the twigs aside for decoration, pluck off the remaining leaves. Wash the ginger, set aside 2 thin slices for decoration, peel the remaining ginger and roughly chop.
Put the ginger, cane sugar and basil with 1/4 of the mineral water in a tall container and puree everything finely. Fill 2 glasses with the ice cubes, pour the lemonade mixture through a sieve into the glasses and add the remaining mineral water. Finally, decorate the glass with the ginger slices and the basil sprigs.
Honey or maple syrup can also be used as an alternative to the cane sugar.