This is hands down the best way to cook a whole chicken to maintain its juiciness and flavor. Spatchcocking the chicken allows it to cook more evenly and allows the smoke flavor to come in contact with more of the chicken.
Spatchcock your chicken following the instructions above.
Preheat your smoker to 300 degrees.
Apply rub to the chicken. Use your fingers to separate some of the skin from the meat and sprinkle some rub beneath the skin.
Cook the chicken to the desired temperature. White meat is best at about 155-165 and dark meat is best at between 175-185. *See note above about safe temps for chicken.
When the skin reaches your desired color, start spritzing with the Parkay to prevent the skin from becoming too dark.
Let the chicken rest for about 5 minutes before serving.
Notes
Typically the chicken cooks in 2-3 hours, but every chicken is different so cook to internal temperature, not time.