01 - Preheat oven to 400°F. Line a baking sheet with parchment paper or lightly grease it.
02 - In a large bowl, combine ground chicken, breadcrumbs, egg, green onions, garlic, soy sauce, ginger, black pepper, and salt. Mix until just combined, being careful not to overwork the meat.
03 - Roll the mixture into 1-inch meatballs and arrange them on the prepared baking sheet with even spacing.
04 - Bake for 18 to 20 minutes until the meatballs are cooked through and lightly golden on the outside.
05 - While the meatballs bake, combine pineapple juice, soy sauce, rice vinegar, brown sugar, and ketchup in a saucepan over medium heat. Bring to a gentle simmer.
06 - In a small bowl, dissolve cornstarch in water to create a slurry. Whisk the slurry into the simmering sauce and cook for 2 to 3 minutes until thickened.
07 - Stir the drained pineapple chunks into the thickened sauce and simmer for an additional 2 minutes.
08 - Transfer the baked meatballs into the saucepan, tossing gently to coat evenly. Cook for 2 to 3 minutes until the meatballs are heated through and well glazed.
09 - Serve hot, garnished with fresh cilantro or parsley, alongside steamed rice or noodles if desired.