Cut the pork belly into bite-sized pieces.
Slice the kimchi and onion into pieces easy to eat.
Stir-fry the pork belly in a pot to render the fat.
Add the kimchi and onion and stir-fry together.
Add gochugaru (Korean red pepper flakes), minced garlic, and soy sauce, and stir-fry.
Pour in water (or broth) and bring to a boil.
Add tofu and green onion, then simmer for 5 more minutes.
Season with salt and pepper to taste.