Preheat your oven to 450°F (232°C).
Pat the spatchcocked chicken dry with paper towels.
In a small bowl, mix together the olive oil, kosher salt, black pepper, garlic powder, onion powder, smoked paprika, dried thyme, lemon zest, and lemon juice.
Rub the spice mixture all over the chicken, making sure to get under the skin for maximum flavor.
Place the chicken skin-side up on a baking sheet or in a roasting pan.
Roast in the preheated oven for 45 to 55 minutes, or until the internal temperature reaches 165°F (74°C) in the thickest part of the breast.
Let the chicken rest for 10 minutes before carving.
Garnish with fresh herbs before serving.