Place the chicken breast between two sheets of parchment paper and pound to an even half-inch thickness.
In a shallow bowl, soak the chicken in the buttermilk for at least 15 minutes to tenderize.
In a separate bowl, whisk together the almond flour, arrowroot starch, smoked paprika, garlic powder, onion powder, sea salt, and black pepper.
Remove the chicken from the buttermilk, letting excess drip off, then dredge thoroughly in the flour mixture, pressing to adhere.
Lightly coat the air fryer basket with avocado oil and place the chicken inside, spraying the top of the chicken with the remaining oil.
Air fry at 400 degrees Fahrenheit for 12-15 minutes, flipping halfway through, until the internal temperature reaches 165 degrees Fahrenheit and the crust is crisp.
While the chicken cooks, steam the green beans for 5 minutes until tender-crisp and bright green.
Serve the crispy chicken immediately alongside the steamed green beans for a balanced, clean-eating feast.