Preheat the oven to 375°F (190°C).
In a small bowl, whisk together the melted butter, olive oil, grated Parmesan, minced garlic, dried basil, dried oregano, dried thyme, and red pepper flakes (if using) until combined.
Pat the chicken breasts dry and season both sides generously with salt and pepper.
Place the chicken breasts in the prepared 9×13-inch baking dish in a single layer.
Spoon the Parmesan-herb mixture evenly over each chicken breast, spreading to coat the tops.
Bake uncovered for 25–30 minutes, or until the chicken reaches an internal temperature of 165°F (75°C).
Remove from the oven and let the chicken rest for a few minutes, then sprinkle with chopped fresh parsley before serving.
