Serious Eats - seriouseats.com

After reading other comments I have few suggestions that may help. First, Rice flour (which is healthier) can be substituded for corn starch and will give the same crispiness. Use 50/50 with flour. Second, put your flour mixture in a paper bag (or plastic grocery bag) and flour your chicken right out of the buttermilk shaking well. Rewmove chicken and place in a bowl, cover with plastic wrap and place in refridgerator for at least 1 hour (2 is better) before frying you will find that the coating becomes very sticky and will not come off while frying. Especially when deep frying. The crispy coating outstanding.
ChefG