Begin by heating a large skillet over medium heat for about 2 minutes. Once hot, add the ground beef, breaking it apart with a spatula. Cook for 5-7 minutes, stirring occasionally, until the beef is evenly browned with no pink remaining. Drain excess fat while keeping a little for flavor.

Add the diced onion to the skillet and sauté for 2-3 minutes, until it becomes translucent and fragrant. Then, stir in the minced garlic, cooking for an additional minute until the aroma fills the kitchen.

Toss in the shredded cabbage, stirring to combine with the beef mixture. Sauté for about 5 minutes until the cabbage starts to wilt while maintaining a slight crunch.

Pour in the soy sauce, sesame oil, rice vinegar, ground ginger, and a pinch of red pepper flakes. Mix well for 2-3 minutes, allowing all the flavors to meld.

Once everything is well combined and heated through, remove the skillet from heat. Garnish with sliced green onions and toasted sesame seeds if desired. Serve hot.