Begin by patting the chicken breasts dry with paper towels. Rub a mixture of 1 tablespoon of coarse salt and 1 teaspoon of ground pepper on the chicken, marinating for at least 30 minutes.
In a separate bowl, whisk together the all-purpose flour, cornstarch, baking powder, paprika, 4 teaspoons of coarse salt, and 1/2 teaspoon of ground pepper. In another bowl, beat the eggs and mix in the buttermilk.
Coat each chicken breast first in the flour mixture, dip it into the egg mixture, and then back into the flour mixture for extra crunch and flavor.
Heat enough oil for frying in a deep frying pan or Dutch oven over medium-high heat until it reaches 350°F (175°C).
Carefully place the coated chicken breasts in the hot oil, frying for about 6-8 minutes on each side, until golden brown and cooked through. Drain on paper towels.
In a small bowl, mix the remaining 1/2 cup of fryer oil, cayenne pepper, honey, chili powder, garlic powder, onion powder, and 2 teaspoons of coarse salt. Brush this spicy sauce over the fried chicken.
Assemble the sandwiches by placing a piece of spicy fried chicken on the bottom half of a toasted bun. Top with coleslaw, pickles, and mayonnaise if desired. Finish with the top bun and serve immediately.