Preheat your oven to 400°F (200°C) and lightly grease a baking sheet with the olive oil.
Place the chicken breast between two sheets of parchment paper and pound it to an even half-inch thickness to ensure it cooks uniformly.
In a shallow bowl, whisk the half egg until smooth; 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 it firmly into the almond flour mixture until it is thoroughly and thickly coated on both sides.
Place the chicken on the prepared baking sheet and bake for 12-15 minutes until the crust is firm and the chicken is nearly cooked through.
Remove the pan from the oven, spoon the marinara sauce over the chicken, and sprinkle with the shredded mozzarella cheese.
Return to the oven and broil for 2-3 minutes until the cheese is bubbly and slightly browned.
Let the chicken rest for 2 minutes, then garnish with freshly chopped basil before serving.