Preheat your oven to 400°F and line a baking sheet with parchment paper for easy cleanup.
Slice the chicken breast into thin cutlets and pound them to an even half-inch thickness using a meat mallet.
In a shallow bowl, whisk the egg until smooth. In a separate shallow bowl, combine the almond flour, grated parmesan, garlic powder, oregano, sea salt, and black pepper.
Dip each chicken cutlet into the egg wash, allowing any excess to drip off, then press firmly into the almond flour mixture to ensure a thick, even coat.
Arrange the breaded chicken on the prepared baking sheet and lightly drizzle or spray with the olive oil.
Bake for 15 to 18 minutes, flipping halfway through, until the crust is golden and the internal temperature of the chicken reaches 165°F.
Remove from the oven, spoon the marinara sauce over each piece of chicken, and top with the shredded mozzarella.
Return the pan to the oven for 3 to 5 minutes, or until the cheese is melted and bubbly.
While the cheese melts, quickly sauté the zucchini noodles in a pan over medium heat for 2 minutes until just tender, then serve the chicken over the noodles.