Place chicken in a large bowl and season with salt and pepper, toss to ensure even coverage.
Set up your dredging station by whisking together eggs, buttermilk and hot sauce in a large bowl, and combine flour and 4 tsp salt in a separate bowl.
Add oil to your deep sided cast iron pan and fill with 2" of oil. Heat on medium high until the temperature reads 350-375 degrees.
Pat chicken dry with paper towel then dredge in flour mixture, shaking off excess, then dredge in buttermilk mixture, letting extra liquid drip off, and finally dredge in flour mixture again. Set each coated piece on a wire baking rack as you work in batches to complete the remaining pieces.
Place chicken in frying oil, working in batches as needed, and fry till golden brown and temperature reaches 165 degrees, turning chicken as needed to ensure even frying. ~5 minutes. Place cooked chicken on a separate wire rack until all chicken has been fried.
Turn off heat and let the oil cool slightly and mix together cayenne, brown sugar, chili powder, garlic powder, and paprika in a bowl. Add 1 cup of frying oil to the mixture and whisk to combine.
Let oil cool slightly and brush oil mixture over each piece of chicken and serve on top of white bread with pickles.