01 -
Add tomato sauce, tomato paste, brown sugar, honey, apple cider vinegar, Worcestershire sauce, liquid smoke, onion powder, garlic powder, black pepper, salt, and red pepper flakes to the slow cooker. Whisk together until fully combined.
02 -
Add frozen meatballs to the slow cooker. Stir gently to ensure all meatballs are evenly coated with the barbecue sauce.
03 -
Cover and cook on low for 4 hours or on high for 2 hours, until meatballs are heated through and the sauce is bubbling.
04 -
Transfer meatballs to a serving dish or keep warm in the slow cooker. Serve with cocktail sticks or as desired.