To make spice rub simply whisk together all of your dry ingredients in a medium bowl until well combined.
Pat the chicken dry with a paper towel and rub it all over with softened butter or olive oil.
Sprinkle dry rub all over the chicken in an even layer (you may have a little left over, save it for rubbing on other meats).
Drink or spill out half of your beer, drop garlic cloves in can, and place the can inside of the chicken cavity, so that that chicken is sitting on top of it, using its legs as support.
Prepare your grill so that one side is hotter than the other (if you have a charcoal grill, place more coals on one side of the grill than the other. If you have a gas grill, only turn burners on on one side). The internal temperature of the grill should be 300-350F.
Place the chicken, perched on its beer can throne, on the cool side of the grill. Close the grill lid and leave the chicken to cook for 1 hour — resist the urge to open the lid and check. Just leave it alone!
After an hour, check on the chicken and make sure your coals don’t need refreshing, or that the temperature hasn't dropped below 300. The chicken will probably need about 30 to 40 more minutes, but insert a meat thermometer into the thickest part of the chicken thigh to check the temperature.
Continue cooking for 30 to 40 more minutes, checking every 10 minutes or so, until the temperature reaches 160° F.
Removing the chicken from the grill can be tricky -- the beer is hot and the chicken is hot -- so be careful. Put on some oven mitts and place a cutting board next to the grill. Slide a large metal spatula under the beer can, grab the top of the chicken with a pair of tongs, and carefully transfer it onto the cutting board.
Let chicken rest for 10 to 15 minutes before carving and serving.
Heat your oven to 350° F. Place your seasoned chicken, balanced on its beer can, in a roasting pan, and place the roasting pan on the lower rack of your oven. Cook until a thermometer reaches 160° F, about 1 1/2 hours.
Lift chicken off of beer can using tongs, and transfer to a cutting board.
Allow the chicken to rest 10 to 15 minutes before carving.
Cara Nicoletti is a butcher and writer living in Brooklyn, New York. Cara started working in restaurants when she moved to New York in 2004, and was a baker and pastry chef for several years before following in her grandfather and great-grandfathers' footsteps and becoming a butcher. She is the writer behind the literary recipe blog, Yummy-Books.com, and author of Voracious, which will be published by Little, Brown in 2015. She is currently a whole-animal butcher and sausage-making teacher at The Meat Hook in Williamsburg.