Preheat your oven to 400°F and line a baking sheet with parchment paper.
Place the chicken breast between two sheets of plastic wrap and pound to an even half-inch thickness.
In a shallow dish, whisk the egg until smooth. In a second shallow dish, combine the almond flour, parmesan cheese, oregano, garlic powder, salt, and pepper.
Dip the chicken breast into the egg wash, letting any excess drip off, then press into the almond flour mixture until fully coated on both sides.
Place the coated chicken on the prepared baking sheet and bake for 15 minutes.
Remove the pan from the oven. Spoon the marinara sauce over the chicken and sprinkle with the shredded mozzarella.
Return the chicken to the oven for another 5 to 7 minutes, or until the cheese is melted and the chicken reaches an internal temperature of 165°F.
While the chicken finishes, quickly sauté the zucchini noodles in a non-stick pan over medium heat for 2 to 3 minutes until just tender.
Serve the hot chicken parmesan immediately over the bed of zucchini noodles.