Whisk the soy sauce, oyster sauce, hoisin sauce, toasted sesame oil, Shaoxing wine or dry sherry, brown sugar, white pepper, and water in a small bowl. Add the red pepper flakes or chili oil if you want heat, and whisk in the cornstarch slurry now if you prefer a thicker sauce.

Cook the fresh or dried lo mein noodles according to the package directions until just tender. Drain them very well and toss with a small amount of oil to prevent sticking; avoid overcooking because they will finish in the pan.

Heat a large wok or skillet over medium-high to high heat, then add the neutral oil and ground beef. Cook for about 5 to 7 minutes, breaking the beef into small pieces, until browned and fully cooked; drain excess fat if necessary.

Add the minced garlic and ginger to the browned beef and stir-fry for about 30 seconds, just until fragrant. Add the carrot, bell pepper, and cabbage, then cook for 2 to 4 minutes so the vegetables become crisp-tender rather than soft.

Add the cooked noodles and prepared sauce to the hot pan. Toss continuously for 2 to 3 minutes until every noodle is coated, the sauce is hot, and the noodles have absorbed some of the savory flavor.

Fold in most of the sliced green onions and remove the pan from the heat. Scatter the remaining green onions and toasted sesame seeds over the lo mein before serving.