Place soy sauce, mirin, sugar, sake and ginger in a pot over high heat and stir until sugar is dissolved. Let it cook for about 3 minutes. Set aside at room temperature.

Clean the chicken breasts, removing as much as possible those small traces of fat that may have and cut it into medium pieces.

As a side dish with the chicken the most common is to use onion that is cooked with the chicken. By always looking for caramelized, this is going to accomplish much of the sugar contained in the teriyaki sauce. In this case we have chosen a big onion, we cut it in julienne in thick strips.

In a large frying pan heat the oil and add the chicken pieces and the onion. Brown for about 5 or 6 minutes. Add the prepared teriyaki sauce and cook over medium heat for 15 minutes. We will see that the chicken is shiny, like lacquered with the sauce, and this has almost been consumed.

When you're going to serve it and a touch of sesame seeds.