In a bowl, toss the sliced cucumbers with salt and let sit for 10 minutes to draw out excess water.
Drain the liquid and gently squeeze the cucumbers to remove remaining moisture.
In a separate bowl, combine garlic, rice vinegar, soy sauce, sugar, sesame oil, and chili flakes.
Add the cucumbers to the dressing and mix well.
Sprinkle with toasted sesame seeds and chopped green onion before serving.