Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.
In a large mixing bowl, combine the ground turkey, breadcrumbs, Parmesan cheese, minced garlic, beaten egg, parsley, salt, and pepper. Mix well until all ingredients are fully incorporated.
Form the turkey mixture into 1-inch meatballs and place them on the prepared baking sheet, ensuring they are evenly spaced.
Bake the meatballs for 20-25 minutes or until they are golden brown and cooked through, reaching an internal temperature of 165°F (74°C).
While the meatballs are baking, prepare the honey garlic sauce. In a small saucepan, combine honey, soy sauce, and rice vinegar. Heat over medium until it starts to simmer.
If you prefer a thicker sauce, mix the cornstarch with a tablespoon of cold water to form a slurry, then add it to the sauce, stirring constantly until it thickens slightly. Remove from heat.
Once the meatballs are done baking, transfer them to a large bowl and drizzle the honey garlic sauce over them. Toss gently until all meatballs are evenly coated.
Serve the meatballs warm, garnished with sesame seeds and sliced green onions.