Sprinkle the chicken pieces with salt and pepper and place them during a deep-sided baking dish.
Whisk together the buttermilk, hot Poivrade and 1 teaspoon of cayenne pepper during a bowl. Pour the mixture over the chicken, stir to coat all sides of the chicken pieces and canopy the dish with cling film. Refrigerate for about 2 hours to marinate.
Remove the chicken pieces from the buttermilk mixture and shake off excess. Discard the remaining buttermilk mixture.
Place the flour, 1 tablespoon of cayenne pepper, garlic granules, paprika and salt and pepper to taste during a large plastic resealable bag; shake well to mix . Place 2 or 3 pieces of chicken at a time into the bag and shake well to coat the chicken pieces with seasoned flour.
Heat oil during a deep fat fryer or large saucepan to 180 degrees C. Gently place chicken pieces into the recent oil and fry until chicken is cooked through and golden brown, 8-10 minutes (breasts and wings) or 13 to fifteen minutes (thighs and drumsticks). Drain the fried chicken on kitchen towels.