1
PREP BEEF: Add the beef, baking soda, cornstarch, and soy sauce to a bowl. Toss everything together and set aside.
2
MIX STIR FRY SAUCE: Combine all of the stir fry sauce ingredients together in a small bowl and set aside.
3
COOKING: Heat the oil in a large skillet over high heat. Add the beef and spread it out and leave it cook for 2 minutes untouched. Toss it around a bit, then add the garlic, ginger, and onion and cook for 2 minutes. Add the mushrooms and cook for another 2 to 3 minutes, just until they start to brown a bit. Pour the sauce over everything and tiss until well coated. Cook for another 2 to 3 minutes to allow the sauce to thicken.
4
Garnish with green onions and serve with rice or over rice.