Wash and dry the cucumbers, then slice into thin rounds. Place in a large mixing bowl or storage container.
Mince the garlic and slice the green onion into thin slices. Add to the cucumbers, along with the soy sauce, sesame oil, gochugaru, sesame seeds, and sugar.
Use tongs or chopsticks to mix all ingredients together, making sure the cucumbers are coated. Cover the bowl or seal the storage container. Refrigerate to enjoy chilled, or serve immediately as a side dish or snack.
