Place the chicken breast between two sheets of parchment paper and pound to an even half-inch thickness to ensure even cooking.
In a shallow bowl, whisk the egg until smooth; in a second bowl, combine almond flour, parmesan cheese, garlic powder, sea salt, and black pepper.
Dip the chicken into the egg wash, then dredge in the parmesan mixture, pressing firmly to ensure a thick golden crust forms.
Heat the olive oil in a large skillet over medium heat and cook the chicken for 5-6 minutes per side until crispy and fully cooked through.
Remove the chicken to a plate and add the sliced zucchini to the same skillet, sautéing for 3-4 minutes until tender-crisp.
Warm the marinara sauce with red pepper flakes in a small saucepan over low heat until steaming and fragrant.
Spoon the zesty marinara onto the center of a plate, top with the crispy chicken, and serve with the sautéed zucchini on the side.