Grate ginger and squeeze juice from pulp, setting juice aside. Combine soy sauce, sake, Mirin (honey) and 2 tbsp ginger juice in a small bowl.
Pour remaining ginger juice (2 tbsp) evenly over chicken, and let marinate in the refrigerator for 15 minutes. Be carful not to overmarinate the chicken or it will fall apart during cooking.
Sprinkle flour over chicken.
Heat oil in a frypan over medium heat, and place chicken skin-side down and cook until the skin turns a nice golden brown. Turn chicken over and let cook several minutes more until done.
Add vegetables, if desired, and pour sauce over chicken. Cover and cook over medium heat for a few minutes.
After a few minutes, the sauce should look something like this. Enjoy!