Begin by bringing a large pot of salted water to a rolling boil. Add the linguine and cook until al dente, usually around 8-10 minutes. Drain and set aside.

In a large skillet over medium-high heat, add the lean ground beef. Cook for about 6-8 minutes, breaking apart until browned. Drain excess fat.

Reduce heat to medium, add minced garlic to the skillet with browned beef, sauté for about 1 minute until fragrant.

Stir in the soy sauce, beef broth, brown sugar, hoisin sauce, ground ginger, black pepper, and red pepper flakes. Let simmer for 2-3 minutes.

In a small bowl, mix cornstarch with 2 tablespoons of water until smooth. Add to skillet, stirring continuously until sauce thickens, about 2-3 minutes.

Add the cooked linguine to the skillet, tossing until well coated in the sauce. Let simmer for 2-3 minutes.

Garnish with sliced green onions before serving immediately.