Finely chop minced meat, onion, green onion, garlic, and tofu.
Heat cooking oil in a pan, add chopped garlic and green onion, and stir-fry until fragrant.
Add the minced meat and cook; once done, add onion and tofu and stir-fry together.
Add gochujang, doenjang, soy sauce, sugar, and chili powder, mixing the seasoning evenly.
Pour in water and doubanjiang or oyster sauce, and bring to a boil.
Add starch water to adjust the thickness.
Season with sesame oil and black pepper, then serve the sauce over rice.