Thinly slice the cucumbers. Place them in a colander and sprinkle with 0.5 teaspoon of salt. Let sit for 10-15 minutes to draw out excess water. Gently squeeze out any remaining water from the cucumbers.
In a medium bowl, whisk together the rice vinegar, sugar, sesame oil, toasted sesame seeds, red pepper flakes (if using), and minced garlic (if using).
Add the prepared cucumbers to the dressing and toss to coat. Allow to marinate for at least 5 minutes before serving.
Serve chilled as a refreshing side dish.
Notes
This salad is best served fresh. You can adjust the sweetness and spice to your liking.