Preheat your oven to 400°F. Line a baking sheet with parchment paper or lightly grease it with cooking spray.
In a large bowl, combine the buttermilk and ranch seasoning mix. Add the chicken breasts, ensuring they are well coated. Cover and refrigerate for at least 30 minutes, or up to 2 hours for more flavor.
In another bowl, mix together the breadcrumbs, garlic powder, onion powder, paprika, salt, black pepper, and Parmesan cheese.
Remove the chicken from the buttermilk mixture, allowing excess to drip off. Dredge each piece in the breadcrumb mixture, pressing gently to adhere. Place the coated chicken on the prepared baking sheet.
Lightly spray the tops of the chicken with cooking spray or drizzle with olive oil to help them crisp up.
Bake in the preheated oven for 25-30 minutes, or until the chicken is cooked through and the coating is golden brown and crispy. The internal temperature should reach 165°F.
Let the chicken rest for 5 minutes before serving.