In a medium size bowl, combine ground pork (1.5 pounds), egg, 2 tablespoon soy sauce, ground ginger (1 tsp), green onions (¼ cup) and salt (½ tsp). Mix lightly with hands until ingredients are combined.
Using a scoop or a tablespoon, shape into 24 evenly sized meatballs. TIP: wet hands slightly before shaping to prevent sticking.
Heat 1 tablespoon oil in a large skillet over medium high heat. Add meatballs and cook until browned on all sides and cooked through to 160 degrees in the center. Remove from pan, set aside.
In a small bowl, combine reserved pineapple juice, 2 tablespoon soy sauce, 2 teaspoon cornstarch, and 1 tablespoon rice wine vinegar. Mix to combine with a whisk.
Heat the same skillet you for the meatballs and heat to medium high heat. Add pineapple juice mixture and bring to a bowl, Stir until thickened, 3-4 minutes.
Return meatballs and add pineapple chunks to the pan and cook until heated through. Simmer on low for 5 minutes. Serve over rice.