Grab a large pot and pour some vegetable oil into it over medium-high heat.
Once the oil is hot enough, you'll want to put in your sliced onions, sliced mushrooms, sliced pork belly/shoulder, minced garlic and ginger. Stir things around for 4 to 5 minutes or until the pork is lightly browned and the vegetables have become softened.
Add in your chopped kimchi pieces and stir things around for another 2 to 3 minutes.
Add in your chicken broth, Korean chili flakes, gochujang, black pepper, salt and sugar. Stir everything together until it is all combined.
Bring the contents to a nice simmer and then cover the pot. Let the contents cook for around 10 to 15 minutes.
Once time is up, uncover the pot and place your tofu into the pot. Then cover the pot again and let it cook for another 10 minutes.
Uncover the pot and garnish with your chopped green onions and sesame oil. Stir things around for a minute or so and then turn off the heat.