Lightly grease the inside of the slow cooker insert with non-stick cooking spray. Transfer the frozen meatballs to the slow cooker.
1 bag of frozen meatballs
In a small bowl, whisk together the beef broth, brown gravy mix, onion soup mix, ketchup, and Worcestershire sauce until well combined. Pour the sauce evenly over the meatballs and gently toss to coat.
2 cups beef broth, 1 packet of brown gravy mix, 1 packet of onion soup mix, 2 tablespoons ketchup, 1 tablespoon Worcestershire sauce
Cover the slow cooker with the lid and cook on low heat for 6 hours, stirring occasionally to ensure even cooking.
Once done, create a slurry by mixing the cornstarch and water in a small bowl until smooth. Pour the slurry into the slow cooker and stir well to incorporate and thicken the sauce.
2 tablespoons cornstarch, 2 tablespoons cold water
Serve the meatballs over a bed of creamy mashed potatoes or egg noodles. Optionally, garnish with chopped fresh parsley for added flavor and color.