How to Make It
Put the rice in a medium saucepan and rinse under cold running water, rubbing the rice with your fingers until the water runs clear. Transfer the rice to a colander and let drain for 30 minutes.
In the saucepan, cover the rice with the water, then cover the saucepan and bring the rice to a simmer over high heat. Reduce the heat to low and cook for 15 minutes. Remove the rice from the heat and let it steam for 5 minutes, until tender. Stir the rice gently with a fork to separate the grains, then cover the saucepan and keep the rice warm until serving.
Meanwhile, in a medium bowl, combine 3 tablespoons of the soy sauce with 1 tablespoon of the mirin, 1 tablespoon of the sake and the ginger. Add the chicken to the bowl, stir to coat and let marinate for 15 minutes.
In a large nonstick skillet, heat the vegetable oil. Coat the chicken slices lightly with the flour and add to the skillet in a single layer. Stir-fry the chicken over moderately high heat until golden brown, about 4 minutes. Transfer the chicken to a plate and keep warm. Wipe out the skillet.
Add the chicken broth, the remaining 2 tablespoons of soy sauce, 2 tablespoons of mirin, 1 tablespoon of sake and the rice vinegar to the skillet. Bring the sauce to a simmer over moderately low heat and cook for 5 minutes. Add the onion slices and simmer over moderate heat, stirring occasionally, until softened, about 5 minutes. Add the bell pepper and cook until softened, about 3 minutes.
Spread the onion and bell pepper slices out in an even layer in the skillet and pour the beaten eggs on top of the vegetables. Spread the cooked chicken over the egg mixture and then top it with half of the scallions. Cook over moderately low heat until the eggs are almost set, 6 to 8 minutes.
Spoon the rice into serving bowls and top with the fried chicken and eggs. Garnish the chicken with the remaining scallion slices and the nori strips and serve immediately.