You'll need a whole fresh dressed chicken to make sous vide spatchcock chicken.
Cut along each side of the chicken's backbone to remove it.
This is how it looks when the backbone is removed.
Turn the chicken over, skin side up, and press down firmly on the breastbone to flatten.
Rub the sous vide spatchcock chicken with oil, salt, pepper and garlic powder.
If using a water bath, vacuum-seal the chicken in a bag. For steam oven sous vide, just pop it onto a tray.
Cook the chicken in the steam oven or water bath for 5-7 hours, then finish under a hot broiler or grill for crispy skin.
Let the chicken rest in a warm spot for 10-15 minutes before carving and serving.