Drain the oil from the tuna using a strainer.
Finely chop the onion, spicy green chili, and green onion.
In a bowl, add the tuna, doenjang (soybean paste), gochujang (red chili paste), chopped vegetables, minced garlic, sesame oil, and sesame seeds.
Mix all the ingredients thoroughly.
Serve the ssamjang on lettuce or perilla leaves, wrap, and enjoy.