Preheat your oven to 400°F and line a baking sheet with parchment paper or lightly grease a baking rack.
In a shallow dish, pour the buttermilk and season with a pinch of salt, pepper, paprika, and garlic powder.
Place the chicken breast between two sheets of plastic wrap and gently pound to an even thickness if necessary.
Submerge the chicken in the buttermilk mixture, ensuring it is well coated. Allow it to marinate in the refrigerator for at least 30 minutes (or up to 2 hours for more flavor).
In a separate shallow bowl, combine the panko breadcrumbs, grated Parmesan, a pinch more paprika, garlic powder, salt, and pepper.
Remove the chicken from the marinade, letting any excess drip off, and dredge it in the breadcrumb mixture, pressing gently so the coating adheres evenly.
Place the coated chicken on the prepared baking sheet or rack. Lightly spray or drizzle a small amount of oil over the top to help crisp the crust.
Bake in the preheated oven for 20-25 minutes, or until the chicken is cooked through and the coating is golden and crispy. The internal temperature should reach 165°F.
Let the chicken rest for a few minutes before serving to lock in the juices, then enjoy your crispy oven-baked buttermilk chicken.