Step 1: In a medium bowl, combine the diced chicken with 1 tablespoon of soy sauce and 1 teaspoon of cornstarch. Toss to coat evenly and set aside to marinate while you prepare other ingredients. In a separate small bowl, whisk together all the sauce ingredients (1/4 cup low-sodium soy sauce, 1 tbsp rice vinegar, 1 tbsp oyster sauce, 1 tbsp brown sugar, 1 tsp sesame oil, 1 tsp cornstarch, 1/4 cup water or chicken broth) until smooth. Set aside.
Step 2: Heat a large wok or skillet over high heat. Add 1 tablespoon of neutral oil. Once shimmering, add the marinated chicken in a single layer. Cook for 3-4 minutes, stirring occasionally, until browned and mostly cooked through. Do not overcrowd the pan; cook in two batches if necessary. Remove the chicken from the pan and set aside.
Step 3: Add the remaining 1 tablespoon of oil to the hot pan. Add the minced garlic and grated ginger. Stir-fry for about 30 seconds, until fragrant, being careful not to burn them.
Step 4: Add the thinly sliced cabbage to the pan. Stir-fry for 3-5 minutes, tossing frequently, until the cabbage begins to wilt but still retains a tender-crisp texture.
Step 5: Return the cooked chicken to the pan with the cabbage. Give the prepared sauce a quick whisk to recombine any settled cornstarch, then pour it over the chicken and cabbage. Toss everything together rapidly, ensuring all ingredients are evenly coated. Cook for another 1-2 minutes, or until the sauce thickens and clings to the ingredients.
Step 6: Remove the Cabbage Stir Fry from the heat. Taste and adjust seasoning if needed. Garnish with sliced green onions and sesame seeds, if desired, and serve immediately with rice or noodles.