CC license
Ingredients:

2 x 300 gm (10 oz) Sirloin steaks, fat free.
60 gm (2 oz) piece of ginger
120 ml ( ½ cup) sake
120 ml ( ½ cup) light soy sauce
60 ml ( ¼ cup) Mirin (a sweet Japanese sake cooking wine with alcohol between 1-14% and 20 -50% sugar)
Brown sugar 2 tbsp
1 tspn Cornflour 
10 ml ( 2 tspn) water


Method:

Grate the ginger and squeeze the ginger juice from the gratings.  Place 15 ml (1 tbsp) of the ginger juice into a mixing bowl with the sake, soy and Mirin. And add the 2 tbspn of brown sugar. Mix it briefly and place aside.

Take the steaks and poke them all over with a fork. This creates cavities which allow the marinade to penetrate the meat.

Pour 120 ml (½ cup) of the marinade into a zip-lock freezer bag followed by the steaks. Express the air. Seal the bags and place in the refrigerator for one (1) hour.


Teriyaki Sauce:

Place the marinade on the heat  and bring to the boil. While waiting for it to boil, mix the 1 tspn of cornflour with the 2 tspn of water and disperse the mixture. 

Drizzle the cornstarch mixture into the sauce and whisk while you add it. The boiling eliminates a lot of the alcohol and the little cornflour will minimally thicken the sauce. Continue boiling for a minute or two. 


Cooking the steak:

Remove the steaks from the marinade bag and pat the meat dry with absorbent paper towels.

Heat a pan with a small amount of oil and place the steaks in the pan. Sear the steak and turn once only. For a rare steak 3 to 4 minutes is probably fine but this is your call. Pour 30 ml ( 2 tabsp) of the sauce directly over the cooking steaks. This will glaze the steaks. 

Remove the steaks from the pan and place on a plate to rest for  5 to 10 minutes.

Slice the steak thinly. Splay the meat on the serving plate and pour some of the sauce over the meat. Sprinkle some sesame seeds and a little green onion as garnish. 

Serve.