Heat enough oil to just cover the bottom of a large wok or frying pan over a medium-high heat. Once the oil is shimmering, add the chicken pieces in batches and fry for a few minutes on each side ...
Take the chicken out of the marinade, gently shaking off excess buttermilk and garlic. Place on the rack, with the thighs skin-side up. Discard the marinade. Roast the chicken for 35–40 minutes ...