Prepare the dressing: In a medium bowl, whisk together the water, rice vinegar, sugar, and salt until fully dissolved.
Prep the cucumbers: Peel the cucumbers, cut them in half lengthwise, and use a spoon to scrape out the seeds. Slice them into thin half-moons and add them to the bowl with the dressing.
Chop the aromatics: Dice the red onion and finely chop the jalapeño. Add both to the bowl.
Slice the basil: Stack the basil leaves, roll them up tightly, and slice them into thin strips perpendicular to the roll (a technique called chiffonade). Add to the salad.
Add the cilantro: Rinse, dry, and chop the cilantro before mixing it in.
Combine and chill: Stir everything together and refrigerate for 30–60 minutes to let the flavors meld.
Serve: Enjoy chilled as a refreshing side dish!
Notes
Enjoy leftovers the next day before the cucumbers become too soft.
Rice vinegar can be found in the international or "Asian" aisle of most grocery stores. Seasoned rice vinegar also works, but I don’t recommend substituting other types of vinegar—rice vinegar is the key to this dish’s signature flavor.