Preheat a smoker to 250 degrees F (120 degrees C).

Mix paprika, chili powder, cayenne, black pepper, thyme, garlic powder, onion powder, and salt together in a large mixing bowl with a fork until thoroughly combined.

Spatchcock chicken by placing the breast down on a work surface. Starting at the tail end, cut along both sides of the backbone with kitchen shears. Remove backbone. Grabbing hold of both sides of the chicken, open it like a book. Turn the breast so it’s facing up. Push down on each side of the breast with your hands until you hear it crack; press to flatten. Rub chicken all over with seasoning blend.

Smoke chicken in the preheated smoker until an instant-read thermometer inserted into the thickest part of the thigh, near the bone, reads 140 degrees F (60 degrees C), about 3 1/2 hours. Turn up the heat to 350 to 400 degrees F (175 to 200 degrees C) and get direct heat on the skin to finish up with an internal temperature of 160 degrees F (71 degrees C), about 15 more minutes.

Remove chicken from the smoker, cover in foil, and allow to rest until the internal temperature reaches 165 degrees F (74 degrees C), about 10 minutes. Cut and serve.