Start by washing the cucumbers thoroughly. Cut off the ends and then slice each cucumber in half lengthwise. Using the flat side of a knife or a rolling pin, gently smash each cucumber half until it cracks but remains intact. Cut the smashed cucumbers into bite-sized pieces and place them in a bowl.
Sprinkle the salt over the cucumbers and let them sit for about 10 minutes to draw out excess moisture. After 10 minutes, gently squeeze the cucumbers to remove any released water and then drain.
In a separate bowl, whisk together the rice vinegar, soy sauce, sesame oil, sugar, grated ginger, and minced garlic until well combined.
Pour the dressing over the drained cucumbers and toss to coat evenly.
Sprinkle the sesame seeds and sliced green onions on top and give it one last gentle toss.
For best flavor, let the salad sit for at least 15 minutes before serving to allow the flavors to meld.