Cucumber and basil cocktail

Method

1. Put most of the cucumber in a large pan with the lemon juice and caster sugar, then tear in most of the basil. Gently simmer until the sugar has dissolved.
2. After a few minutes, remove from the heat and set aside to cool. Once completely cool, strain through a fine sieve, pour into a clean bottle or jar and seal securely.
3. Serve topped up with still or sparkling water, garnished with the remaining cucumber slices and basil leaves (or see Make Ahead).