If the meat is not pre-sliced, you will want to slice it fairly thin.
Gather all of your marinade ingredients and mix them all together in a large bowl.
Add the meat, and toss the meat with the marinade so it is evenly coated.
Add the onion and the green onion, and toss everything together again.
Now you can let it sit for about 30 minutes, or you can cover it with plastic wrap and place it in the fridge overnight. This way, the marinade has ample time to flavor the meat.
Grill or pan fry in a skillet (in 2 batches) or more, depending on how much you are making.
You want to cook over medium-high heat until the meat is slightly caramelized. Even though it looks really good right off the grill, you are going to want to wait at least a minute or two. That way, you don't burn your mouth.
Enjoy.