Slice the cucumber and onion into bite-sized pieces. Cut the cucumber diagonally and slice the onion thinly.

Drain the sea snail can completely and remove the snails. Cut them into bite-sized pieces.

Prepare the sauce by mixing 1 tbsp gochujang, 1 tbsp vinegar, 1 tbsp sugar, 1 tbsp red pepper powder, and 1/2 tbsp minced garlic.

Place the sliced cucumber, onion, and sea snails in a large mixing bowl.

Pour the prepared sauce over the ingredients gradually while mixing thoroughly.

Finish by adding 1 tbsp sesame oil and a sprinkle of sesame seeds for a nutty aroma.