In a large mixing bowl, combine ground beef, panko breadcrumbs, egg, 2 tbsp soy sauce, 1 tbsp grated ginger, 2 minced garlic cloves, 1 tbsp sesame oil, 1 tsp gochujang, and black pepper.

Gently mix until just combined, being careful not to overmix, which can make the meatballs tough.

Roll the mixture into 1-inch to 1.5-inch meatballs (approximately 24-30 meatballs), placing them on a parchment-lined baking sheet.

Preheat oven to 400°F (200°C).

Bake meatballs for 18-22 minutes, or until cooked through and lightly browned. (Internal temperature should reach 160°F/71°C).

Air Fryer Option: Cook at 375°F (190°C) for 12-15 minutes, shaking the basket halfway, until cooked through.

While meatballs are cooking, prepare the glaze. In a small saucepan, combine 1/2 cup soy sauce, 1/4 cup gochujang, mirin, brown sugar, rice vinegar, 1 tbsp sesame oil, 1 tbsp grated ginger, and 2 minced garlic cloves.

Whisk well and bring the mixture to a simmer over medium heat. Cook for 3-5 minutes, stirring occasionally, until the sugar has dissolved and the sauce slightly thickens.

In a small bowl, whisk together cornstarch and 2 tbsp water to create a slurry.

Pour the cornstarch slurry into the simmering glaze, whisking constantly. Continue to cook for another 1-2 minutes until the sauce has thickened to a syrupy consistency. Remove from heat.

Once the meatballs are cooked, transfer them to a large bowl.

Pour the prepared Korean BBQ glaze over the meatballs and toss gently until all meatballs are evenly coated.

Garnish with chopped green onions and sesame seeds before serving.