Coat the Chicken – Toss the sliced chicken in cornstarch, ensuring each piece is evenly coated. Shake off excess.
Cook the Chicken – Heat vegetable oil in a pan over medium-high heat. Cook the chicken until golden and crispy, about 4-5 minutes per side. Remove and set aside.
Make the Sauce – In the same pan, sauté garlic and ginger until fragrant. Add soy sauce, water, brown sugar, rice vinegar, sesame oil, and red pepper flakes. Stir and let it simmer for 2 minutes.
Combine & Thicken – Return the cooked chicken to the pan, tossing it in the sauce until well coated. Simmer for 2-3 minutes until the sauce thickens.
Garnish & Serve – Add chopped green onions and sesame seeds. Serve hot over steamed rice or noodles.