In a small bowl, whisk together soy sauce, water, brown sugar, honey, mirin, sesame oil, and cornstarch until smooth.
Heat vegetable oil in a large skillet over medium-high heat. Add minced garlic and ginger, sautéing for about 1 minute until fragrant.
Add the sliced beef to the skillet and cook for about 2-4 minutes until browned.
Pour the sauce mixture over the beef. Stir well to coat the beef evenly. Adjust sauce seasoning, adding more brown sugar if needed.