Drain the oil from the canned tuna and prepare it.
Finely chop the onion, Cheongyang chili pepper, and green onion.
In a bowl, mix the tuna, chopped vegetables, soybean paste (doenjang), red chili paste (gochujang), minced garlic, and sesame oil together well.
Add toasted sesame seeds and mix once more thoroughly.
Serve on lettuce or perilla leaves as a wrap.