Peel cucumbers to leave alternating green stripes
Slice the cucumbers in half lengthwise and scrape the seeds out with a spoon
Using a sharp knife, cut into very thin slices
Place a double layer of paper towels and squeeze gently to remove an excess moisture
Combine vinegar, sugar, and salt in a medium bowl, stirring to dissolve
Add the cucumbers and sesame seeds; toss well to combine
Serve immediately