Prepare the Brine: In a large mixing bowl, whisk together buttermilk, salt, black pepper, garlic powder, poultry seasoning, paprika, and hot sauce until well combined.
Brine the Hens: Place the Cornish hen halves in a resealable plastic bag and pour in the buttermilk mixture. Seal the bag, ensuring the brine coats all pieces evenly. Refrigerate for at least 3 hours or up to 24 hours for the best flavor.
Heat the Oil: In a deep pan or fryer, heat peanut oil to 325°F using a deep-fry thermometer to ensure accurate temperature control.
Prepare the Flour Mixture: In a large dish, combine flour, salt, black pepper, paprika, garlic powder, cayenne, and poultry seasoning. Mix well to distribute the seasonings evenly.
Dredge the Chicken: Remove one hen piece at a time from the brine, allowing excess liquid to drip off. Coat the hen thoroughly in the flour mixture, pressing the flour into the skin to ensure a crispy crust.
Fry in Batches: Carefully lower two pieces into the hot oil at a time. Fry for 12 to 15 minutes, turning every 3 to 4 minutes, until the internal temperature reaches 165°F.
Drain and Serve: Remove the fried hens from the oil and let them drain on a wire rack or paper towels for 5 minutes before serving. Enjoy while hot!