Begin by boiling a pot of water and cooking the lo mein noodles according to the package instructions, reducing the cooking time by 1-2 minutes for perfect tenderness.

In a medium bowl, whisk together the beef broth, low sodium soy sauce, brown sugar, hoisin sauce, black pepper, and cornstarch. Set this flavorful sauce mixture aside.

Preheat a large griddle or skillet over medium-high heat, then add the lean ground beef, allowing it to sear undisturbed for 2-3 minutes before breaking it apart and fully cooking.

Add the chopped white parts of the green onions to the skillet, stirring until the beef is fully cooked and the green onions are tender, about 2 minutes.

Drizzle high-heat cooking oil into the skillet, sprinkle in the reserved minced garlic and ginger, and sauté for about 30 seconds.

Add the drained lo mein noodles to the skillet and allow them to cook, untouched, for 1-2 minutes to slightly crisp up.

Pour the prepared sauce over the noodles and beef mixture, stirring to coat everything and cooking for an additional 2-3 minutes until thickened.

Transfer the Mongolian Ground Beef Noodles to plates and garnish with the remaining green onion tops. Serve immediately.