In the afternoon the day before you plan to cook the chicken, brine chicken pieces in 8 cups cold water combined with the salt. Store in refrigerator for two hours.
Drain the chicken, pat dry, and then soak in buttermilk in the refrigerator overnight.
In a large ziploc bag, combine flour with black pepper, cayenne pepper, and baking powder. Shake well. Remove chicken from buttermilk and pat dry. Shake the chicken pieces in the Ziploc bag, a few pieces at a time. Shake off excess flour.
Melt shortening in a deep skillet, adding enough so that you have a shallow pool of oil, about 1 inch deep or less. (Don’t add too much because the oil will bubble up when you add the chicken.) Bring the oil to 375 degrees, and then begin cooking the chicken pieces, a few at a time, turning occasionally, until the internal temperature of the chicken is 165 degrees. Drain chicken on a baking rack over brown paper bags until all excess grease has dripped off. Serve hot or cold. Serves 8.