Whisk together chicken broth, soy sauce, oyster sauce, hoisin sauce, brown sugar, rice vinegar, chili garlic sauce, and sesame oil in a bowl

Heat vegetable oil in a large skillet or wok over medium-high heat

Add chicken pieces in a single layer

Cook for 5–7 minutes, turning occasionally, until lightly browned

Remove chicken from the pan and set aside

Add chopped onion to the same pan

Cook for 3–4 minutes until softened

Add garlic and ginger

Stir constantly for about 30 seconds until fragrant

Return chicken to the pan

Pour in the prepared sauce

Bring to a gentle simmer

Reduce heat to medium-low and cook for 10 minutes

Mix cornstarch and water in a small bowl

Stir slurry into the chicken

Cook for 2–3 minutes until sauce thickens and coats the chicken

Adjust thickness with a splash of broth if needed

Remove from heat and serve hot over rice