Mongolian Beef Ingredients 1 lb skirt steak, thinly sliced against the grain 1/4 cup cornstarch 1/2 cup water 1/2 cup low-sodium soy sauce 1/4 cup packed light brown sugar 1/2 teaspoon red pepper flakes 3 teaspoons canola oil, divided 1/2 teaspoon grated ginger 1 tablespoon minced garlic (about 2-3 cloves) 2 scallions, thinly sliced