Empty out (or drink!) half of the can of beer. Place the can in an upright chicken roaster.
Drop the garlic cloves into the beer can.
Carefully fit the chicken over the roaster so that the beer can is snug within the cavity of the chicken.
Oven Method:
Preheat the oven to 350 degrees. Adjust the oven rack to the lower third of the oven.
If your roaster does not have a drip pan, place the roaster in a pie plate or casserole dish.
Place the chicken on the roaster, standing up, into the oven
Bake for 18 minutes per pound, until an instant read thermometer reaches 165 - 170 degrees.
Remove chicken from the oven. Allow to rest 15 minutes before serving.
Grill Method:
Prepare grill for indirect heat - once the briquettes have enough ash on them, pile the briquettes to one side, leaving a "cool" side. If using a gas grill, turn on all burners until grill reaches 350 degrees, then turn off the burners on one side.
Place chicken on the “cool” side of the grill.
Roast for 1-1/2 – 2 hours, rotating about halfway through cooking time, until an instant read thermometer measures an internal temperature of 180 degrees.
Remove chicken from the grill. Allow to rest 15 minutes before serving.
For the sauce:
Pour the beer left in the can into a saucepan. Mix with the salsa and simmer until heated through. Serve on the side as a dipping sauce.
Notes
Storage: Leftover cast iron roast chicken should be cooled completely before transferring the carved meat to an airtight container. Store in the refrigerator and consume within four days.Reheat: Leftover chicken can be reheated for a few in the microwave. Alternately, place the meat in a covered casserole dish and bake at 350 degrees for 10-15 minutes until heated through.Freeze: Place leftover meat in an airtight freezer bag. Consume within three months.