1. Preheat oven to 325 degrees Fahrenheit (160 degrees Celsius). Wash roast, pat dry, and place in a 9×13-inch baking pan. Lightly season with onion powder, garlic powder, seasoned salt, and paprika. Cover pan and cook for one hour.
2. While roast is cooking, place barbecue sauce ingredients in a small saucepan. Stir and bring to a boil, then simmer for two minutes.
3. Pour the barbecue sauce over the roast and return it to the oven, uncovered. Bake an additional hour and a half (two hours if over three pounds), basting every 15 minutes.