Instructions

1. In small saucepan, whisk together soy sauce, sake, sugar, vinegar, ginger and hot pepper flakes. Bring mixture to boil and allow to cook over high heat until thickened into glaze, approximately 5 minutes.   
2. Taste and adjust seasoning, if needed. Set aside half of sauce in small bowl for serving with finished meatballs. Keep remainder of sauce covered with aluminum foil until step 6.
3. In large bowl, mix well-ground white and dark turkey, white onion, ginger, garlic, sea salt and 1-1/2  teaspoons sesame oil.  
4. Using hands, form meat mixture into generous 1-tablespoon round meatball. Place on parchment-lined baking sheet.  Repeat process until all meat is made into meatballs.
5. To large skillet, add 2 teaspoons sesame oil.  Add half (about 20) of meatballs to skillet and cook on medium heat for about 5 minutes.  Turn meatballs over, and cook for an additional 5 minutes.
6. Brush half of set-aside covered sauce over meatballs. After 1 minute, flip each meatball over with tong, and brush other side with sauce. Cook another 1 minute, or until glazed and cooked completely through. If sauce darkens too quickly, reduce heat.  
7. Insert bamboo skewer into each meatball and place on serving platter.
8. Sprinkle with sesame seeds and sliced scallions.
9. Serve immediately.