In a four cup measuring cup or small bowl mix together the barbecue sauce ingredients: ketchup, brown sugar, finely chopped yellow onion, apple cider vinegar, beef broth, sea salt, coarse ground black pepper, ground paprika, ground cumin and worcestershire sauce.

Pour enough of the barbecue sauce into the bowl of your slow cooker to cover the bottom. Set the rest aside.

In a mixing bowl blend together the ground beef, bread crumbs, egg, parmesan cheese, grated onion, minced garlic, tomato paste, sea salt, coarse ground black pepper and chili powder with your hands or a spoon.

Form the meatball mixture into golf ball sized balls and place them in your slow cooker. Do not stack any of them on top of each other. Make sure you have them on the bottom of the slow cooker bowl.

Pour the remaining barbecue sauce over the meatballs.

Cover your slow cooker and cook on low for 3-4 hours. Meatballs should be browned and a minimum of 160 degrees on the inside when tested with a thermometer.

Serve hot as an appetizer or over buttered pasta or with mashed potatoes for dinner.