Heat sesame oil in a large skillet over medium-high heat until shimmering. Add minced garlic and ginger, cooking for about a minute until fragrant. Stir constantly so they don’t burn and become bitter.
Add ground beef to the skillet, breaking it up as it cooks. Let it sit briefly before stirring to allow browning. The browned bits give a rich, deep flavor to the dish.
Mix in salt, pepper, and soy sauce, coating the beef evenly. Taste and adjust seasoning. The soy sauce brings a gentle saltiness without overpowering the dish.
Add the chopped cabbage and stir frequently until tender but still slightly crisp, about 5–7 minutes. The cabbage will soak up flavors while retaining a light crunch.
Top with chopped green onions and optional red pepper flakes. Serve hot for best flavor, enjoying the mix of warm beef and fresh aromatic garnish.