Preheat your oven to 400°F and line a baking sheet with parchment paper.
Place the chicken breast between two pieces of plastic wrap and pound to an even half-inch thickness using a meat mallet or heavy skillet.
In a shallow bowl, whisk the half egg; in a second shallow bowl, combine the almond flour, parmesan cheese, garlic powder, oregano, sea salt, and black pepper.
Dip the chicken breast into the egg wash, then press into the almond flour mixture until thoroughly and evenly coated on both sides.
Place the coated chicken on the prepared baking sheet and bake for 15 minutes.
Remove the chicken from the oven, spoon the marinara sauce over the top, and sprinkle with the shredded mozzarella cheese.
Return the chicken to the oven for an additional 5 minutes, or until the cheese is melted and bubbling.
While the chicken finishes, spiralize the zucchini into noodles and sauté them in a pan with olive oil over medium heat for 2-3 minutes until just tender.
Plate the zucchini noodles and top with the baked chicken parmesan to serve.