Preheat your air fryer to 375°F (190°C).
Slice the chicken breast into even strips and place them in a small bowl with the buttermilk, tossing to coat thoroughly.
In a separate shallow dish, whisk together the almond flour, arrowroot starch, garlic powder, onion powder, smoked paprika, sea salt, and black pepper.
Remove each chicken strip from the buttermilk, letting excess drip off, then dredge in the flour mixture, pressing firmly so the coating adheres.
Place the coated chicken in the air fryer basket and lightly mist with avocado oil spray.
Air fry for 12-15 minutes, flipping halfway through, until the crust is golden brown and the internal temperature reaches 165°F.
While the chicken cooks, steam the green beans and cauliflower florets until they are tender-crisp.
Serve the crispy chicken immediately alongside the steamed vegetables.