Wash the cucumber, then either slice it into thin rounds or blend it, depending on whether you prefer a chunky or smoother drink.

If you blend it, you can also strain it for a cleaner texture.

Add the lemon juice and sweetener, then stir to combine.

Gently press the mint leaves to release their aroma, then add them to the drink.

Pour in the water or sparkling water, then stir well.

Serving: Pour into glasses over ice, then garnish with cucumber slices and fresh mint.