In a large bowl, whisk together the buttermilk, 1 tablespoon of salt, 1 teaspoon of black pepper, garlic powder, and paprika. Add the chicken pieces to the bowl, ensuring they're fully submerged in the buttermilk mixture. Cover and refrigerate for at least 4 hours, or overnight for best results.

Remove the chicken from the refrigerator at least 30 minutes before you plan to fry it, allowing it to come to room temperature. This ensures more even cooking.

In a large shallow dish, mix the all-purpose flour with the remaining 1 teaspoon of black pepper, cayenne pepper (if using), and additional salt to taste.

Lift a piece of chicken out of the buttermilk, allowing the excess to drip off. Dredge the chicken in the flour mixture, coating it thoroughly. Shake off any excess flour and set the coated chicken on a wire rack. Repeat with the remaining chicken pieces.

Fill a large, deep skillet or Dutch oven with about 1 inch of vegetable oil. Heat the oil to 350°F (175°C) over medium heat. Use a deep-fry thermometer to check the temperature.

Carefully place several pieces of chicken in the hot oil, being careful not to overcrowd the pan. Fry the chicken in batches if necessary. Cook until golden brown, turning once, about 10 to 15 minutes per side. The internal temperature of the chicken should reach 165°F (74°C) when done.

Adjust the heat as necessary to maintain the oil temperature between 300°F (150°C) and 325°F (165°C) during frying.

Use tongs to transfer the fried chicken to a clean wire rack set over a baking sheet (or paper towels) to drain any excess oil.

Let the chicken rest for a few minutes before serving. Fried chicken can be enjoyed hot, at room temperature, or even cold.