Remove neck and giblets from the cavity if they are included.
Place chicken on a cutting board, breast side down so the backbone is facing up. Using scissors, cut along each side of the backbone to remove it completely.
Flip the chicken over so the breast side is up. Using your palms, press on the breast bone to flatten it. It should crack as it flattens. Fold the wing tips under the chicken.
Place on a large baking sheet and brush with olive oil. Sprinkle generously with seasoning.
Roast the chicken for 45-50 minutes or until it reaches 165°F internally.
Remove from the oven and let rest for 10 minutes before carving.