Butterfly the chicken by removing its rib bone and pressing down on the breasts until the chicken flattens.
Pour pesto sauce from the jar and into a bowl. Stir in the olive oil.
Generously season chicken on both sides and under the skin with Tony’s seasoning.
Flip chicken so that it’s skin-side down. Using a bristle basting or pastry brush, coat the chicken in the pesto sauce. Turn the chicken skin-side up and continue to coat the chicken, and under the skin.
Cook the chicken in the oven at 425 degrees for 30-45 minutes, then at 450 minutes for another 10-15 minutes, or until the chicken is cooked through and skin is crispy.
Remove the chicken from the oven, squeeze with fresh lemon juice, garnish with chopped herbs and serve.