Clean the oysters thoroughly.
Cut zucchini, onion, tofu, green onion, and Cheongyang chili peppers into bite-sized pieces.
Pour kelp broth or anchovy stock into a pot and bring to a boil.
Dissolve the doenjang (soybean paste) into the broth.
Add zucchini, onion, and tofu to the pot and cook.
Once the vegetables are cooked, add oysters, green onion, Cheongyang chili peppers, and minced garlic. Simmer for a little longer.
Taste and adjust seasoning with salt or soup soy sauce if necessary.