Start by spraying the slow cooker insert with nonstick cooking spray.

Place the frozen meatballs directly into the slow cooker.

In a mixing bowl, combine the reduced-sodium beef broth, brown gravy mix, onion soup mix, ketchup, and Worcestershire sauce and whisk until smooth.

Carefully pour the gravy mixture over the meatballs and stir to coat.

Cover and set the slow cooker to LOW for 5 to 6 hours.

Once cooking time is up, mix cornstarch with cold water until smooth and stir it into the slow cooker.

Cover and let it cook for an additional 10 minutes.

Serve the meatballs over mashed potatoes or egg noodles and garnish with chopped parsley.