In a medium bowl, whisk together the beef broth, soy sauce, brown sugar, minced garlic, cornstarch, sesame oil, onion powder, and black pepper until the cornstarch is fully dissolved.
1 Cup beef broth, ½ Cup Soy Sauce, ⅓ Cup Brown Sugar, 3-5 cloves Garlic, 3 tablespoons Cornstarch, 2 tablespoons Sesame Oil, ¼ Teaspoon Onion Powder, ¼ Teaspoon Black Pepper