01 - If the chicken breasts are thick, gently pound them to an even thickness of about 1/2 inch using a meat mallet.
02 - In a large bowl, whisk together the buttermilk, egg, salt, black pepper, garlic powder, and paprika until well combined.
03 - Add the chicken breasts to the marinade, cover, and refrigerate for at least 30 minutes or up to 4 hours for deeper flavor penetration.
04 - Arrange two shallow dishes: in the first, combine the flour, breadcrumbs, salt, smoked paprika, and cayenne pepper. Remove the chicken from the marinade, shaking off any excess.
05 - Dredge each marinated chicken breast in the flour-breadcrumb mixture, pressing gently to ensure an even, adherent coating on all sides.
06 - Heat the vegetable oil in a large skillet or frying pan over medium-high heat until shimmering and the temperature reaches 350°F.
07 - Carefully place the coated chicken breasts in the hot oil and fry for 5 to 7 minutes per side until golden brown and crispy, reaching an internal temperature of 165°F.
08 - Transfer the fried chicken to a paper towel-lined plate to drain excess oil. Allow to rest for 2 to 3 minutes before serving.