A porridge (Okayu) that resembles a thin risotto, gently flavored with a hint of warming ginger.
Place water in a pot and bring it to a boil. Add the chicken and cook until fully cooked. Remove the chicken, let it cool, and shred it into small pieces. Set aside.
Slice the green onion very thinly and set it aside.
Season the broth with sake, mirin, soy sauce, salt, and grated ginger. Add the rice and cook for a few minutes until the mixture slightly thickens.
Top with chicken and onion and serve immediately.