In a small bowl, whisk together brown sugar, reduced sodium soy sauce, sesame oil, crushed red-pepper flakes, and ground ginger until smooth. Set it aside.

Heat vegetable oil in a large skillet over medium-high heat. Add minced garlic and sauté for about 1 minute until fragrant.

Add ground beef to the skillet, breaking it apart with a spatula. Cook for 3-5 minutes, crumbling as it browns until fully cooked.

Pour the sauce mixture over the cooked ground beef, stirring well to ensure everything is coated evenly. Simmer for about 2 minutes.

Stir in thinly sliced green onions and cook for an additional minute.

Serve immediately over freshly cooked rice or in lettuce wraps, garnished with sesame seeds and additional green onions.