Preheat a grill pan over medium-high heat. In a small mixing bowl, mix together 4 tablespoons of the melted butter, garlic powder, onion powder, salt, and pepper. Brush each chicken breast with the melted butter mixture.
6 tablespoons unsalted butter, 1 teaspoon garlic powder, 1 teaspoon onion powder, ½ teaspoon salt, ½ teaspoon pepper, 2 boneless skinless chicken breasts
Place the chicken breasts on the preheated grill pan and cook for 3-4 minutes, then flip the chicken.
In a medium mixing bowl, mix together ½ cup of the Parmesan cheese and provolone cheese, and set it aside.
¾ cup grated Parmesan cheese, ½ cup shredded provolone cheese
Top the chicken with the cheese mixture, and cook for another 3-4 minutes until the internal temperature reaches 165°F.
Remove the chicken from the grill pan and place it on a baking sheet lined with foil.
Preheat your oven's broiler on high.
In a separate medium mixing bowl, mix the panko breadcrumbs with the remaining Parmesan cheese (¼ cup) and remaining 2 tablespoons melted butter. Sprinkle the buttered panko breadcrumbs evenly over the top of each chicken breast.
¾ cup grated Parmesan cheese, ½ cup Panko breadcrumbs, 6 tablespoons unsalted butter
Place the baking sheet under the broiler for 1-2 minutes or until the breadcrumbs are golden and crispy. Watch carefully to prevent burning.
Remove the chicken from the broiler and let it rest for 5 minutes before serving.