Season London Broil thoroughly with salt and pepper on both sides and place in a slow cooker.
Add garlic, onions, beef broth, and soy sauce to the top of the meat
Cook on low 9-10 hours hours.
Remove the meat to a separate dish and allow meat to rest 10 minutes or until the internal temperature reads 120 degrees Fahrenheit.
Remove meat to a separate dish and pour liquid into a sauce pan.
Mix 2 tablespoons of cornstarch with 2 tablespoons of cold water or beef broth and mix.
Stir into saucepan and simmer until thickened, stirring often.
