It’s so easy to make vegetable lo mein, a Chinese take-out favorite, at home—and it’s lighter and less heavy on the oil than its restaurant counterpart.
Cook the noodles according to package directions in plenty of rapidly simmering water until al dente, then drain.
Meanwhile, heat the safflower oil, broth, or water and 1 teaspoon of the sesame oil (if desired) in a stir-fry pan. Add the cabbage, broccoli, and green beans. Cover and cook for 2 to 3 minutes.
Add the mushrooms, if desired, and scallions and stir-fry over medium-high heat for 5 minutes or until the vegetables are just tender-crisp. Add a small amount of vegetable broth or water, just enough to keep the pan moist.
Add the cooked noodles to the stir-fry pan and toss together. Add the remaining teaspoon of sesame oil, if using, then season with soy sauce and pepper to taste. Serve at once.