Place the chicken breast in a shallow bowl and pour the buttermilk over it, letting it marinate for 15 minutes.
In a separate wide dish, whisk together the almond flour, arrowroot powder, garlic powder, onion powder, smoked paprika, sea salt, and black pepper.
Remove the chicken from the buttermilk, allowing the excess to drip off, then press firmly into the flour mixture until fully coated.
Preheat your air fryer to 375°F and lightly coat the basket with the avocado oil.
Place the breaded chicken in the basket, spray the top with the remaining oil, and air fry for 12 to 15 minutes, flipping once, until the crust is golden and crunchy.
While the chicken is cooking, steam the cauliflower florets and green beans in a steamer basket until they are fork-tender.
Transfer the steamed cauliflower to a blender or use a masher to create a smooth, creamy consistency, adding a tiny pinch of the sea salt if desired.
Plate the crispy chicken alongside the cauliflower mash and green beans for a balanced, wholesome feast.