In a large stock pot, place chicken and cover with water, one tablespoon garlic powder and one teaspoon of onion powder. Cook on medium-high heat till the pot comes to a boil. Reduce heat, cover and simmer for 15 minutes.
While chicken is cooking, combine ketchup, one cup brown sugar, mustard, chili powder and remaining garlic and onion powders in a small sauce pan over medium heat. Simmer for 15 minutes adding liquid smoke and remaining brown sugar to your taste.
Once chicken has simmered, place on medium-high heated grill. Grill for 30-40 minutes or till chicken reaches an internal temp of 165. Baste with barbecue sauce as it grills.