Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper or a silicone baking mat.
In a bowl, combine Parmesan cheese, breadcrumbs, garlic powder, Italian seasoning, salt, and pepper.
Pat the chicken breasts dry. If using the egg, beat it in a small bowl.
Dip each chicken breast in olive oil (or egg, if using).
Press it into the breadcrumb mixture, ensuring all sides are evenly coated.
Place the coated chicken breasts on the prepared baking sheet. Bake for 20–25 minutes, flipping halfway through, until the chicken is golden and reaches an internal temperature of 165°F.
Let the chicken rest for 5 minutes before serving.