Slice the chicken breast into even strips or keep as a thin cutlet for uniform cooking.
Place the chicken in a bowl with the buttermilk and let marinate for at least 15 minutes.
In a shallow dish, whisk together the flour, garlic powder, onion powder, smoked paprika, sea salt, and black pepper.
Remove each piece of chicken from the buttermilk, letting excess drip off, then dredge thoroughly in the seasoned flour mixture.
Heat the avocado oil in a large skillet over medium-high heat until shimmering.
Carefully place the chicken in the skillet and cook for 4-5 minutes per side until the coating is golden brown and the internal temperature reaches 165°F.
While the chicken cooks, steam the green beans until tender-crisp and bright green.
Serve the crispy chicken immediately alongside the steamed green beans.