Wash the cucumber with coarse salt or peel it with a potato peeler. Slice it into thick rounds. Cut the chives into 5 cm pieces, slice the onion thinly, and cut the green onion into rounds.

Mix all seasoning ingredients together to create a flavorful sauce: gochujang, chili powder, fish sauce, sugar, vinegar, sesame oil, minced garlic, and sesame seeds.

Add the prepared cucumber, onion, and green onion to the sauce. Gently mix without crushing the vegetables.

Add the chives and mix well to combine all ingredients.