1. To prepare meatballs, combine first 9 ingredients in a bowl; shape meat mixture into 30 meatballs. Heat a large nonstick skillet over medium-high heat. Add half of meatballs to pan; cook 3 minutes or until browned, stirring frequently. Place browned meatballs in an electric slow cooker. Repeat procedure with remaining 15 meatballs.
2. To prepare sauce, combine tomato paste and next 7 ingredients (through tomatoes). Add to slow cooker, stirring gently to coat. Cover and cook on LOW for 6 hours. Serve over couscous. Garnish with parsley, if desired.