Preheat the grill to medium-high heat.
Wash the chicken inside and out with cold water and pat dry with paper toweling. Rub the chicken inside and out with the Napoleon® Creole Cajun Spice, rubbing the seasoning into the meat so it adheres.
Open the beer can and pour about ¼ of the liquid into a small saucepan and set saucepan aside.
Place the opened can onto the center of the Napoleon® Chicken Roaster base. Assemble Napoleon® Chicken Roaster according to manufacturer’s instructions. Place the seasoned chicken over the can so that the can is in the cavity of the bird and the bird is standing upright. Tuck the wing tips in behind the chicken, ensuring they are secure.
Place the chicken on the Napoleon® Chicken Roaster onto the grill. Close the lid and roast for 1-1½ hours, about 20 minutes per pound. Baste liberally with BBQ sauce throughout the last half of cooking time. To check for doneness, insert a meat thermometer into the thigh. It should read 180°F.
Meanwhile, prepare the basting sauce. Bring reserved beer in saucepan to a boil over high heat. Reduce heat to medium-low and simmer for 1-2 minutes. Add butter and stir until melted. Stir in Napoleon® Fire Roasted Garlic Sauce and heat, stirring well, until incorporated. Remove from heat and set aside until needed.
Carefully remove the chicken from the grill. Allow to cool slightly and remove chicken from roaster very carefully with tongs and a large fork, keeping the Napoleon® Chicken Roaster upright on a flat surface. Chicken will be very hot and there will be steam. Cut chicken into quarters and serve immediately with extra basting sauce on the side.