Trim off the ends of the cucumbers and cut them into bite-sized pieces. Transfer to a mixing bowl. Finely chop the garlic cloves and thinly slice the green onion (if using).
Make the dressing: In a small container, combine all the dressing ingredients with the minced garlic. Mix until smooth and well combined.
Pour the dressing over the cucumbers, add 1 tablespoon of freshly ground sesame seeds, and gently toss until everything is evenly coated. Taste and add more salt if needed. Enjoy!
