Mix sugar, paprika, mustard, cumin, garlic powder, onion powder, cayenne, salt and pepper together. Place ingredients in large plastic zip-lock bag. Place chicken wings into the bag and shake until all chicken is coated; transfer to slow cooker. Pour ½ cup of the barbecue sauce over chicken and stir to coat. Cover and cook until chicken is tender, 3-4 hours on low for wings, 4-6 hours on low for drumsticks.
1 Tablespoon brown sugar, 1 Tablespoon sweet paprika, 1 teaspoon dry mustard, 1 teaspoon ground cumin, 1 teaspoon garlic powder, 1 teaspoon onion powder, ¼ teaspoon cayenne pepper, 1 teaspoon salt, 1 teaspoon pepper, 4 pounds chicken wings and drummettes,, 1 ½ cups barbecue sauce,