Slice cucumbers thinly, about 1/8 inch thick, and place in a colander. Sprinkle with salt and let rest for 10 minutes.

In a mixing bowl, whisk rice vinegar, soy sauce, chili flakes, sugar, and sesame oil until combined. Add minced garlic if using.

Rinse the cucumbers under cold water and drain. In a large bowl, combine cucumbers with the dressing and toss to coat.

Chop green onions and sprinkle over the cucumbers along with sesame seeds. Toss gently to mix.

For the best flavor, refrigerate for at least 15 minutes before serving.

Give the salad a final toss before serving and sprinkle additional sesame seeds on top.