Finely chop the onion, zucchini, and Cheongyang chili pepper.
Drain the oil from the tuna.
Heat a pan, add sesame oil, and sauté the onion and zucchini.
Add the tuna and cook, then add soybean paste.
Pour in water (or broth) and stir well.
Add the Cheongyang chili pepper and simmer on low heat to adjust the consistency.
Add minced garlic at the end and boil once more.