I've struggled with this recipe because I've been trying so hard to get it right. I am a little defiant when it comes to sticking a beer can up the rump of the chicken. The biggest problem that I've had is the brine, and making sure that it's the right concentration of ingredients. Guess no more, here it is, adapted from a recipe in Suzanne Goin's Sunday Suppers at Lucques.
Brine for grilling poultry, pork
Take a big Georgia cup (quart) of hot water, bring to a boil in a stockpot of some kind.
Add 1/2 cup of kosher salt, 1/4 cup of granulated sugar
2 tbsp of ground pepper, red pepper flakes, and thyme
When it all dissolves, add three more quarts to make 1 gallon total.
Spatchcock and clean your chicken, add to the brine. Let it sit at room temperature for about 2 hours or so.
You don't need to drain it or dry it, just throw it on the grill.
The grill setup:
Inverted double decker grill with a 12 inch pizza pan and new high absorption roasting pans that I found at the grocery store(low profile, works GREAT as a drip pan). This is my new indirect setup.
Get your grill going at 400-450 (mostly open bottom, 1/4" slit on top), and throw the chicken on bone side down.
Wait till it reaches around 175 and flip.
Heat to around 195 with the probe on a bone. The bone side of the meat runs cooler and is more likely to be undercooked.
JW describes refrigerating the chicken uncovered to let it dry out before you grill it, and I'm sure that works. However, I found that the skin was pretty crispy as long as a I let it reach that higher temperature, and I didn't even have to squeeze any of the water out of it.
Be careful letting your temperature any higher when you're doing indirect, because your drip pan will catch on fire and go nuts.
Use your giblets and backbone to make home-made chicken stock. You can brown them with some veggies (mire poix carrots, two onions, and celery, thyme and black pepper) along with some water. Do not use the liver for this.
I've also screwed it up trying to cook it skin side down first without flipping, bone side down without flipping, etc. This has given me the best result.
Artificial sweetener, honey, brown sugar can be substituted in the brine, along with whatever else you might want to add. Be careful adding alcohol because it can screw up the moisture and flavor.