We're going to start and end with a marinade. So to begin, pour up a cup of Soy Sauce and 1/2 cup water. Add a couple of pressed garlic cloves, the tsp or 2 of molasses, 2 TBS of plain Splenda, and fine grate/rasp about 2" of fresh peeled ginger. I keep fresh ginger in the freezer so it's always on hand and can easily be grated frozen. The addition of 1 Tbs Mirin (rice wine) makes it even better. Look for it near the soy sauce and Asian brand products in any grocery. We're going to use half this mixture to marinate a flank steak and half of it we'll save for the finishing sauce. Don't pour all of it on the flank steak intending to strain it off later because you'll be surprised how much the meat absorbs!
Now, the trick to cutting flank steak the right way, across the grain, and getting it really thin is this: put it in the freezer until it just begins to get stiff, not hard frozen or you'll never get a knife through it. If you have an electric knife this job will fly!
Lay the knife at an angle across the grain, cut about 1/4" thin, then cut those pieces into squares about 2x2, so it will cook fast enough without toughening up as it browns. Now marinate all those cut pieces in a plastic bag for a couple of hours.
When ready to cook I spray a big skillet with Pam or just barely coat with olive oil. Grab a handful of the beef, squeeze out the marinade, then brown the meat on medium high heat with space in between every piece so they won't just steam in the released juices. That brown coating is so much of the flavor in this recipe. I flip every piece separately to get a good brown but watch closely and take them out just as soon as they're cooked through. This is the closest way to imitate wok fried beef with oil, without using the oil.
THE SHOPPING LIST
1 Flank Steak
1 cup Soy Sauce
2 Cloves Garlic
2 tsp molasses
2" fresh peeled ginger
2 Tbs Splenda
1 Tbs Mirin (rice wine)
1 bunch green onions (scallions)