Slice chicken breasts into small strips and place in a bowl. add teriyaki sauce and sprinkle with half of the spring onions. set aside to marinate for 30 minutes.
In a large bowl, mix together vinegar, sugar, and salt. Pour this vinegar mixture into the rice and mix well.
in a hot pan, add oil and sauté marinated chicken. add mushrooms, season and set aside.
In a bowl, beat eggs and fry. Cut into strips.
In an oiled baking dish/pan, spread an even layer of rice at the bottom. Layer chicken teriyaki over the rice. sprinkle furikake, scrambled eggs, cheese, and spring onions.
Bake at 176°C for 10-15 minutes.