Trim chicken of any fat. For chicken breasts, since they are thicker, I poke them with a fork all over so the marinade can soak in.
In a large bowl, mix soy sauce, water, brown sugar, onions, garlic, sesame oil, and coconut milk.
Pour marinade over chicken and marinate for at least four hours, overnight is preferred. (for chicken breasts, I would definitely say over night is best to ensure the flavor is greatly absorbed)
Grill chicken until chicken is cooked through, switching sides half way through.
It is delicious over coconut rice, garnished with green onions and any additional soy sauce if needed!
To make coconut rice: Replace half of the water in your rice recipe with coconut milk.