In a small mixing bowl, add Dashi, Soy Sauce, sweetener and Japanese sake. Mix well and set aside.
Thinly slice onions and set aside.
Cut chicken into small bite-size pieces, about 1/2 x 1/2 inch and set aside.
In a small mixing bowl, beat eggs and set aside.
In a medium fry pan, add onions on medium heat. Cook for 30 seconds.
After 30 seconds, lower heat to medium low and add chicken and pour sauce. Cover and cook for 4-6 minutes or until chicken is cooked.
Slowly pour beaten eggs into the fry pan. Cook until desired egg consistency is reached and pour chicken/egg mixture over bowl of rice. Traditional, the eggs are a bit runny, but this would be personal preference. Sprinkle optional Togarashi and chopped green onions on top and serve.