In a large skillet over medium-high heat, brown the ground beef for 5-7 minutes, stirring occasionally until it's fully cooked and no longer pink.

Drain any excess fat from the skillet, then add the finely diced onion. Sauté for 2-3 minutes until the onion becomes translucent.

Stir in the minced garlic and ground ginger, cooking for about 1 minute until fragrant.

Add the shredded green cabbage to the skillet, cooking for 4-5 minutes until it's tender yet still slightly crunchy.

In a small bowl, whisk together the soy sauce, sesame oil, rice vinegar, and optional red pepper flakes. Pour this mixture over the beef and cabbage.

Finish by garnishing your dish with sliced green onions and optional toasted sesame seeds.