In a large bowl, whisk together the soy sauce, honey, rice vinegar, minced garlic, grated ginger, and sesame oil until the honey dissolves.
Add the chicken drumettes to the bowl and turn them to coat evenly. Cover and refrigerate for at least 30 minutes or up to 4 hours.
Heat the oven to 400°F and line a baking sheet with foil. Arrange the drumettes in a single layer on the sheet, reserving the leftover marinade.
Bake for 25 minutes. While the drumettes cook, pour the reserved marinade into a small saucepan and bring it to a simmer over medium heat for 3 to 4 minutes until it thickens slightly.
Remove the drumettes from the oven, brush them with the thickened sauce, and return them to the oven for 5 more minutes.
Transfer the drumettes to a serving plate and sprinkle with sesame seeds and sliced green onions before serving.