Soak pork bones for a minimum of 30 mins. 3-4 hours is recommended with a few water changes.
Bring a pot of water to a boil. Blanch the pork bones for 7 minutes.
Strain the bones and rinse each bone under cold water. Place the bones into the Instant Pot.
Add in ginger, Korean soybean paste, shitake mushrooms, onion, dried chili flakes, and water until ingredients are just covered (about 6 cups).
Pressure cook on Manual at high pressure for 30 minutes. Natural release for 20 minutes.
While the broth is cooking, make the seasoning paste. Combine garlic, Korean hot pepper flakes, Korean hot pepper paste, fish sauce, perilla seeds flour, ground black pepper and 1/4 cup water. Stir to combine.
Once the broth is done, remove the shitake mushrooms and slice thinly.
Return mushrooms to the pot, and add potatoes, bean sprouts, napa cabbage, green onions and the seasoning paste.
Pressure cook on Manual at high pressure for 5 minutes. Immediately quick release.
Add the perilla leaves and stir. Serve with chopped green onion as garnish.