Thaw, wash, and pat dry your whole chicken. Locate the top of the backbone and turn the chicken over so it is breast side down.
Using sharp kitchen shears, cut along each side of the backbone until you can remove it completely.
Turn the chicken over and pull out the legs and thighs so it is lying flat. Press down on the breast bone until you hear a crack. The chicken should be lying relatively flat with all the skin showing.
Rub the olive oil and salt and pepper all over the chicken. Place it on a foil lined cookie sheet. Leave the chicken as is or baste it with your favorite BBQ sauce (my recipe follows). Bake it at 425 degrees for 25-30 minutes.
Remove the chicken and baste again with BBQ sauce. Return to the oven for 10 minutes. Repeat this step 3 or 4 more times until the chicken has reached an internal temperature of 165 degrees and is charred and crispy on the edges of the skin. (4 lb chickens will take another 30 minutes and 6 lb chickens may need 30 to 40 minutes).
Remove the chicken, baste one more time, and let the chicken rest 10 minutes before cutting. To cut, start by cutting off the thighs and legs as a whole. Then cut off the wings. Finally, cut between the breasts and remove the breast meat. Serve immediately with extra BBQ sauce.