In a large bowl add the buttermilk and half of each of the spices and mix. In a separate bowl, add the flour and the rest half of the spices. Add the chicken in the buttermilk mixture and marinade for up to two hours
Remove the chicken from the bowl and pat dry
In Dutch oven or a deep cast iron skillet, add some cayenne, paprika, red chili flakes, and garlic powder, and toasts until fragrant. Add oil and heat over a medium-high flame until it reaches 325 degrees
Coat the chicken with the flour-spice mixture, one piece at a time, until it is evenly covered
Add the chicken (as many as you can fit in the fryer maintaining a little space), skin down, frying until crisp and dark golden brown on both sides, about 8 minutes each side
Repeat until all chicken is fried
Place on a wire rack and allow to cool.
Brush with Korean chili paste on both sides
Serve with biscuits and pickle