Preheat your oven to 400°F and line a baking sheet with parchment paper for easy cleanup.
Butterfly the chicken breast by slicing it horizontally to ensure even thickness, then season both sides with sea salt and black pepper.
In a shallow bowl, whisk the half egg; in a second bowl, combine the almond flour, grated parmesan, dried oregano, and garlic powder.
Dip the chicken into the whisked egg, then press firmly into the almond flour mixture until the chicken is thoroughly coated.
Place the coated chicken on the prepared baking sheet, mist lightly with olive oil, and bake for 15-18 minutes until the crust is golden and the chicken is cooked through.
While the chicken bakes, spiralize the zucchini into long noodles and sauté them in a pan with a splash of water for 2-3 minutes until tender-crisp.
Spoon the marinara sauce over the baked chicken and top with shredded mozzarella, then return to the oven under the broiler for 2 minutes until the cheese is bubbly.
Arrange the zucchini noodles on a plate, place the crispy chicken parmesan on top, and serve immediately.