Preheat gas or charcoal grill for medium heat. If you’re using charcoal, you want indirect heat to start and you can move the chicken over direct heat later to get it crispy.
Turn your chicken over and use kitchen shears or a good sturdy knife to cut down the backbone of the bird. If you cut on both sides of the backbone, you should be able to remove it. You can save it for stock if you want.
Flip the bird over and flatten it with your hands until it lays mostly flat and rub it well on both sides with your favorite dry rub. (You can do this in advance and let the chicken rest for up to a day in the fridge to let the rub penetrate and season the bird.)
When you’re ready to cook, rub the grill with some oil (I just use paper towels). Also oil a square of heavy duty foil.
Place the chicken, breast side up, on the grill. Cover it with the oiled foil and a heavy pot or pan (like a cast iron skillet – the foil just keeps the dirty pot from touching the chicken). Cover the grill and let the bird cook for 15-18 minutes.
Remove the weight and foil from the bird and carefully flip it. Replace foil and weight and grill for another 15-18 minutes.
At this point, test the chicken with a meat thermometer. You are looking for 165 degrees F in the thickest part of the thigh. If it isn’t at that temperature yet, flip the bird again and let it cook for another few minutes. Depending on how dark the skin is, you may also want to leave it skin-side down to continue to crisp up the skin.
Once the chicken reaches the right temp, remove it from the grill carefully and loosely cover it with foil. Let it rest for 10 minutes.
Then chop the chicken into large pieces. I usually cut off the wings and have them as a chef snack, then I cup off the thigh and leg on each side and cut the breasts in half.