Put the chicken pieces into a large bowl. Cover the chicken with water by 1-inch; add 1 tablespoon of salt for each quart of water used. Cover and refrigerate at least 2 hours or overnight.
In a large shallow platter, mix the flour, garlic powder, onion powder, paprika, and cayenne until well blended; season generously with salt and pepper. In another platter combine the buttermilk and hot sauce; season with salt and pepper.
Drain the chicken and pat it dry. Dredge the pieces, a few at a time, in the flour mixture, then dip them into the buttermilk; dredge them again in the seasoned flour. Set aside and let the chicken rest while you heat the oil.
Put about 3 inches of oil into a large deep pot; it should not come up more than half way. Bring the oil up to 375 degrees F over medium high heat. Working in batches, carefully add the chicken pieces 3 or 4 at a time. Fry, turning the pieces once, until golden brown and cooked through, about 20 minutes. Remove from the oil and place on a rack to drain; repeat with the remaining pieces.