01 -
Spray your slow cooker with nonstick cooking spray. Layer the onions and mushrooms on the bottom and add the frozen meatballs on top
02 -
In a mixing bowl, whisk together beef broth, brown gravy mix, onion soup mix, Worcestershire sauce, and ketchup. Pour the mixture over the meatballs
03 -
Cover and cook on low for 5–6 hours or on high for 3–4 hours
04 -
About 30 minutes before serving, whisk together cornstarch and cold water to make a slurry. Stir this into the slow cooker, cover, and cook for another 10–15 minutes until the gravy thickens
05 -
Serve the meatballs with gravy over mashed potatoes, egg noodles, or rice. Garnish with fresh parsley, if desired