01 - If the chicken breasts are thick, place each one between two sheets of plastic wrap and gently pound with a meat mallet to an even ½-inch thickness throughout.
02 - In a large bowl, whisk together the buttermilk, egg, kosher salt, black pepper, garlic powder, and paprika until fully combined.
03 - Submerge the chicken breasts in the marinade, turning to coat evenly. Cover the bowl and refrigerate for at least 30 minutes or up to 4 hours for deeper flavor penetration.
04 - In a shallow dish, combine the flour, panko breadcrumbs, salt, smoked paprika, and cayenne pepper. Mix well to distribute the seasonings evenly throughout the coating.
05 - Remove each chicken breast from the marinade, letting excess drip off. Dredge in the flour-breadcrumb mixture, pressing firmly on all sides to ensure a thick, even coating adheres completely.
06 - Pour the vegetable oil into a large skillet or deep frying pan and set over medium-high heat. Allow the oil to reach 350°F—it should shimmer and a small breadcrumb dropped in will sizzle immediately.
07 - Carefully lower the breaded chicken breasts into the hot oil. Fry for 5 to 7 minutes per side until deeply golden brown and crispy. The internal temperature should register 165°F when checked with a meat thermometer.
08 - Transfer the fried chicken to a paper towel-lined plate to drain excess oil. Let rest for 2 to 3 minutes before serving to allow juices to redistribute.