Cook spaghetti according to package directions until al dente. Drain and set aside.
In a mixing bowl, combine ground pork, grated potato, and chopped green onions.
Season the mixture with soy sauce, iodized rock salt, and black pepper. Mix thoroughly until well combined.
Form tablespoon-sized portions of the mixture into round meatballs.
Heat oil in a frying pan over medium heat. Fry meatballs until golden brown on all sides.
Remove meatballs from pan and set aside on paper towels to drain excess oil.
In a saucepan, bring spaghetti sauce to a simmer.
Add the fried meatballs to the sauce and simmer for 5 minutes.
Serve the meatballs and sauce over the cooked spaghetti.
Top with grated cheese if desired.