In a large bowl, measure out the salt. Thinly slice the cucumbers using a mandolin or sharp knife, then as you're cutting them, toss the slices in with the salt so they start to soften while you cut the rest.
Once the cucumbers are all sliced and tossed in the salt, chop up the green onions and add them to the bowl too.
Add the vinegar, toasted sesame oil, and sugar (if using), and mix well to coat. Let it sit for 10-15 minutes if you have time, since it will give the cucumbers a really nice, classic, soft-yet-crunchy texture.
Serve your Japanese cucumber salad sprinkled with toasted sesame seeds. Enjoy! ❤️