1. Mince garlic, ginger, and scallions in a food processor. In a bowl, gently combine garlic mixture with ground beef and salt. Form mixture into 20 meatballs, each 1 1/4 inch in diameter. Chill at least 1 hour and up to overnight.

2. Heat sesame oil in a large skillet over medium high. Add meatballs and cook, frequently shaking the skillet to turn them, until browned and cooked through, about 7 minutes. Remove meatballs to plate. Add soy sauce, honey, and vinegar. In a small bowl, whisk cornstarch into 3 tablespoons water and stir into skillet, scraping brown bits from the bottom. Cook until sauce is thickened, about 30 seconds to 1 minute. Return meatballs to skillet, toss to coat. Serve immediately, topped with scallions and sesame seeds.