Preheat your oven to 400°F and line a baking sheet with parchment paper for easy cleanup.
Butterfly the chicken breast and pound it to an even half-inch thickness to ensure uniform cooking.
In a shallow bowl, whisk the egg white until slightly frothy; in a second bowl, combine the panko, parmesan, oregano, garlic powder, sea salt, and black pepper.
Dip the chicken into the egg white, allowing any excess to drip off, then press firmly into the panko mixture until both sides are thoroughly coated.
Place the breaded chicken on the prepared baking sheet, drizzle with olive oil, and bake for 15 minutes.
Remove the chicken from the oven, spoon the marinara sauce over the top, sprinkle with mozzarella, and bake for an additional 5-7 minutes until the cheese is bubbly and golden.
While the chicken finishes, briefly sauté the zucchini noodles in a pan over medium heat for 2-3 minutes until just tender, then serve the crispy chicken directly on top.