Preheat the oven to 400°F / 200°C and brush the chicken breasts with olive oil, then season with garlic powder and black pepper.
Bake the chicken on a lined baking sheet for 20 minutes until cooked to 165°F / 74°C at the thickest part.
Mix the Parmesan cheese, panko breadcrumbs, and melted butter in a small bowl until combined.
Spread 2 tablespoons of ranch dressing over each cooked chicken breast, then press the Parmesan mixture evenly on top.
Broil on high for 2 to 3 minutes until the crust is golden and crisp, watching closely to prevent burning.
Rest for 3 minutes before serving to let the juices settle and the crust firm up.