Preheat your oven to 400°F and line a small baking sheet with parchment paper for easy cleanup.
In a shallow bowl, whisk the half egg until smooth; in a second bowl, combine the almond flour, parmesan cheese, garlic powder, oregano, sea salt, and black pepper.
Dip the chicken breast into the egg wash, allowing any excess to drip off, then press firmly into the almond flour mixture until both sides are thoroughly coated.
Place the breaded chicken on the prepared baking sheet, drizzle with olive oil, and bake for 15 to 18 minutes until the internal temperature reaches 165°F.
Remove from the oven, spoon the marinara sauce over the chicken, top with the mozzarella cheese, and broil for 2 minutes until the cheese is bubbly and slightly browned.
While the chicken rests, lightly sauté the zucchini noodles in a non-stick pan over medium heat for 2 minutes until tender-crisp, then serve the chicken directly on top.