In a large mixing bowl, combine the ground chicken, breadcrumbs, grated Parmesan cheese, egg, chopped green onions, minced garlic, salt, and pepper. Mix gently but thoroughly until well incorporated, being careful not to overmix.
Form the mixture into 1-inch meatballs, about the size of a golf ball, and place them on a plate or baking sheet.
Heat 1 tablespoon of sesame oil in a large skillet over medium heat. Add the meatballs in batches without overcrowding. Cook for about 4-5 minutes per side until browned and cooked through. Remove from skillet and set aside.
In a small saucepan, whisk together soy sauce, honey, rice vinegar, grated ginger, and one clove of minced garlic. Bring to a gentle simmer over medium heat and cook for 3-4 minutes until sauce thickens slightly.
Return the cooked meatballs to the skillet, pour the teriyaki sauce over them, and toss gently to coat. Let simmer together for 2-3 minutes to absorb flavors.
Prepare the sticky rice according to package instructions or using a rice cooker. Fluff the rice before serving.
Spoon sticky rice onto plates or bowls, top with teriyaki meatballs, and garnish with sesame seeds and extra chopped green onions.