In a large mixing bowl, combine the buttermilk, 2 of the whole eggs, salt, black pepper, and paprika. Whisk until well blended. Submerge the cut-up chicken in the marinade, ensuring each piece is well-coated. Cover the bowl and refrigerate for at least 2 hours, or overnight for maximum flavor and tenderness.
Set up your breading station by placing the flour in a shallow dish. In another bowl, beat the remaining egg with a splash of water or milk. This will create your egg wash.
Remove the chicken from the marinade and allow any excess buttermilk to drip off. Dip each piece into the flour, shaking off any excess, then into the egg wash, and finally back into the flour for a second coating. This double-dipping technique ensures a thick, crunchy crust.
In your cast iron skillet or heavy-bottomed pot, pour enough oil to reach about 1 to 1.5 inches deep. Heat the oil over medium-high heat until it reaches 350°F (175°C). You can test the oil by dropping in a small piece of bread; if it sizzles and bubbles, the oil is ready.
Carefully add a few pieces of chicken to the hot oil, making sure not to overcrowd the pan. Fry the chicken for about 12-15 minutes, turning occasionally, until the pieces are golden brown and cooked through. The internal temperature should reach 165°F (75°C) for safe consumption.
Once the chicken is done, use tongs to transfer it to a wire rack set over a baking sheet. This allows excess oil to drain off while keeping the chicken crispy. Season with additional salt to taste.
Serve your crispy fried chicken hot with your favorite sides, such as coleslaw, mashed potatoes, or cornbread.
