Preheat your oven to 400°F (200°C).

In a large bowl, combine ground meat, breadcrumbs, green onions, egg, and garlic.

Mix until well combined, then form the mixture into meatballs (about 1 inch in diameter).

Place the meatballs on a baking sheet lined with parchment paper.

Bake the meatballs for 15-20 minutes, until cooked through.

Prepare the teriyaki sauce by combining soy sauce, brown sugar, rice vinegar, sesame oil, and ginger in a saucepan.

Cook over medium heat, stirring until the sugar dissolves and the sauce thickens slightly (about 5 minutes).

Remove the meatballs from the oven and toss them in the teriyaki sauce.

Return the coated meatballs to the oven for an additional 5 minutes.

Garnish with sesame seeds before serving.