01 - Preheat oven to 400°F. Lightly grease a 9×13-inch baking dish with olive oil or nonstick spray.
02 - Pat the chicken breasts dry with paper towels. Drizzle with olive oil and season both sides evenly with salt, black pepper, and garlic powder.
03 - In a medium mixing bowl, combine the ricotta cheese, Parmesan, mozzarella, parsley, dried basil, crushed red pepper flakes, and egg. Stir until all ingredients are thoroughly incorporated.
04 - Arrange the seasoned chicken breasts in a single layer in the prepared baking dish. Divide the ricotta mixture evenly and spread it over the top of each breast.
05 - Spoon marinara sauce over the ricotta-topped chicken. Sprinkle the remaining mozzarella cheese evenly across the surface.
06 - Bake uncovered for 30 to 35 minutes, until the chicken reaches an internal temperature of 165°F and the cheese is golden and bubbly.
07 - Remove from the oven and let rest for 5 minutes. Garnish with additional fresh parsley if desired, then serve warm.