Step 1

Season sliced steak with salt and pepper. Toss steak in cornstarch until fully and evenly coated. Set aside.

Step 2

Place a large skillet over medium-high heat and add 1 tablespoon oil. Add garlic and ginger and sauté for 1 minute. Add soy sauce, water and sugar and bring to a boil until sugar dissolves, about 2 minutes.

Step 3

Pour sauce into a liquid measuring cup and set aside.

Step 4

Place skillet back over heat and add remaining oil. Add steak and sear until evenly browned on both sides, 1 to 2 minutes per side.

Step 5

Pour sauce back into skillet and stir together with beef. Simmer and allow sauce to thicken, 1 to 2 minutes.

Step 6

Toss in green onion and continue to cook for 1 more minute until sauce is thick enough to coat the back of a wooden spoon.

Step 7

Pour Mongolian beef over steamed rice and serve.