This Mongolian Beef is luscious in every way. Sweet, savory, tender, and saucy. Be sure to cut beef thinly across the grain for superb tenderness. Have all ingredients measured and prepared so that your cooking process goes quickly and easily!
To make the sauce, heat 4 tsp vegetable oil in a saucepan over med-low heat, until hot but not smoking. Add ginger and garlic to the pan, stir for 30 seconds, and quickly add soy sauce and water.
Add brown sugar in the sauce, stir well, and bring to boil at medium heat 2-3 min. Sauce should thicken a little. Remove from heat and set aside.
Slice flank steak against the grain into 1/4 inch thick bite-size slices. To get nice cuts, tilt blade of knife at 45 degree angle.
Toss steak pieces into a large bowl with cornstarch. All pieces should be coated. Let beef sit 20 minutes (this step helps tenderize the beef.) Add 1/2 tsp table salt and toss to coat.
Meanwhile, heat 1 cup oil in a large wok or large skillet. Heat oil over medium heat until hot but not smoking. Add beef to pan and stir frequently, 2-3 minutes or until beef browns on the exterior. Beef will not be completely cooked, but remove with slotted spoon and place onto paper towel lined plate. Pour oil out. Throw the meat back into the empty pan and stir over medium-low heat for 1 minute. Add the sauce, cook and stir for 1 minutes. Add green onions. Cook 1 minute, stirring, until beef is fully cooked through and onions are wilted.
Serve beef over your favorite rice, with desired amount of sauce.
*Note: If you prefer a bit of kick, add 2-3 dried chilies into the beef during browning in the wok.