01 - Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper or lightly grease it.
02 - In a large bowl, combine the ground meat, breadcrumbs, egg, minced garlic, chopped green onions, cilantro (if using), salt, pepper, soy sauce, and sesame oil. Mix gently until all ingredients are just incorporated.
03 - Shape the mixture into 20–24 small meatballs. Arrange them on the prepared baking sheet and bake for 18–20 minutes, or until cooked through and lightly browned.
04 - While the meatballs bake, prepare the sauce. In a medium saucepan, combine pineapple juice, soy sauce, brown sugar, rice vinegar, grated ginger, and minced garlic. Bring to a simmer over medium heat, stirring occasionally.
05 - In a small bowl, whisk together cornstarch and water to create a slurry. Gradually stir this slurry into the simmering sauce. Continue to cook for 2–3 minutes, stirring, until the sauce has thickened.
06 - Stir the drained pineapple tidbits into the thickened sauce and simmer for an additional 2 minutes.
07 - Once the meatballs are cooked, carefully transfer them to the saucepan with the sauce. Gently toss to coat each meatball evenly. Simmer together for 2–3 minutes to allow the flavors to meld.
08 - Serve the pineapple teriyaki meatballs hot. Garnish with sliced green onions and toasted sesame seeds. For a complete meal, serve over steamed rice if desired.