Combine beef and garlic in a small bowl; mix well. Set aside.
Combine beef broth, Teriyaki sauce and cornstarch in a small bowl. Set aside.
Heat peanut oil in a wok over high heat. Add beef and stir fry quickly, stirring constantly for one minute. Add onion and broccoli; stir fry 3 to 4 minutes. Add beef broth mixture and continue stirring until mixture is thickened and bubbly. Serve with hot white rice. Yield: 2 servings.
Note: Pork tenderloin may be substituted for the beef tenderloin.