Place the chicken breast in a shallow bowl and pour the buttermilk over it, ensuring it is fully coated; marinate for at least 20 minutes.
In a separate wide dish, whisk together the almond flour, arrowroot starch, garlic powder, onion powder, smoked paprika, sea salt, and black pepper.
Remove the chicken from the buttermilk, letting the excess drip off, then dredge it thoroughly in the flour mixture until evenly coated.
Heat the avocado oil in a medium skillet over medium-high heat until shimmering.
Add the chicken to the skillet and cook for 5-6 minutes per side, or until the coating is golden-brown and the internal temperature reaches 165°F.
Remove the chicken from the pan and set aside to rest on a plate.
Reduce the heat to low and pour the chicken bone broth into the same skillet, scraping up any browned bits from the bottom.
Whisk in the Greek yogurt until the sauce is smooth and slightly thickened, then stir in the fresh parsley.
Pour the creamy gravy over the crispy chicken and serve immediately.