In a large bowl, combine buttermilk, garlic powder, paprika, cayenne pepper (if using), and salt. Add the chicken, cover, and refrigerate for at least 2 hours or overnight.

Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper. Place a wire rack on top and spray it with nonstick spray. Mix panko, flour, smoked paprika, oregano, garlic powder, onion powder, salt, and black pepper in a separate dish.

Remove the chicken from the marinade, let excess drip off, then dredge each piece in the breadcrumb mixture. Place coated chicken on the wire rack.

Bake for 35-40 minutes, flipping halfway through, until coating is golden brown and chicken reaches an internal temperature of 165°F (75°C).

Let the chicken rest for 5 minutes. Garnish with parsley and serve with lemon wedges.