Place all the chicken brine ingredients in a pot and bring to a boil.
Boil the brine for 1 minute, until the salt dissolves, then chill it completely. If you’re in a hurry, you can place the mixture in a bowl and set that in an ice bath. Otherwise, let it chill to room temperature, then place it in the fridge.
Once the mixture is chilled, place the chicken in the brine for 8 hours. Try not to go beyond 8 hours or the chicken will get too salty.
Discard the brine and pat the chicken very dry with paper towels. Let the chicken sit at room temperature for 1 hour while you prep the other ingredients.
Mix the flour with the garlic powder, onion powder, paprika, cayenne, salt, and pepper. Split this between two bowls. Place the buttermilk in a third bowl, and set it in between the two spiced flour bowls.
Using either a dedicated deep fryer or a heavy-bottomed pot at least 10" wide and checking the temperature with a thermometer, add enough tallow to come a few inches up the pot. Preheat the temperature to 320F.
In the meantime, bread the drumsticks and thighs by dipping each piece into the flour mixture, shaking off the excess, then the buttermilk, shaking off the excess, then the flour mixture again.
Fry the drumsticks and thighs for 10 minutes, until golden brown and 170F inside, then drain on paper towels.
Raise the fryer heat to 340F. Dip the wings and breasts into the flour, shake off the excess, then the buttermilk, shake off the excess, then the flour again.
Fry the wings and breasts for 6 to 7 minutes, until golden brown and cooked to 160F, then drain on paper towels. Enjoy!
*Make sure to get a small 3 pound fryer chicken (don’t go larger than 4 lbs), that way the pieces don’t overbrown before cooking through. The 10 piece cut is when you separate the whole bird into 2 thighs, 2 drumsticks, 2 wings, and then the 2 breasts are cut in half, so you have 4 breast pieces. If you don't want an assortment of pieces, you can also choose only one type of cut, like all chicken thighs, all chicken breast, etc.**While Thomas Keller recommends frying oils like soybean oil, peanut oil, etc, I prefer to use tallow (beef fat), which is a much more stable fat, has a better flavor, and is far healthier than the other oils. Tallow will also keep the breading much crispier and prevent the exterior from getting soggy. You will likely need at least 6 cups of tallow to come a few inches up the side of the pan, though this varies slightly depending on the size pan you use. Leftovers: Refrigerate in an airtight container for up to 5 days.Reheating: Warm in a 300F oven, uncovered, for 10-15 minutes.Freezing: Store in an airtight container for up to 2 months. Thaw overnight in the fridge before reheating.