Stage one — brine
Why brining changes the meat
Chicken loses moisture as it cooks, and lean cuts like tenderloin lose it fastest. A brine puts salt and liquid back into the muscle before frying, so there is more water to lose before the meat turns dry.
Buttermilk does double duty: the acid tenderizes the surface slightly while the dairy coats the meat and helps the flour stick. Timing matters more than most people expect — thirty minutes in buttermilk is enough for cutlets and nuggets. Bone-in pieces benefit from a few hours, and overnight is fine if you keep them cold. Past a day, the texture starts to go soft in a way that reads as mushy rather than tender.