Instructions:
- Combine buttermilk, 1 Tbsp salt, 1 tsp pepper, and 1 tsp smoked paprika. Submerge chicken thighs completely. Cover and refrigerate for a minimum of 4 hours, up to 24 hours.
- In a large bowl, whisk together flour, cornstarch, garlic powder, onion powder, 2 tsp cayenne, 1 tsp brown sugar, 1 tsp black pepper, and baking powder to create the dredge mixture.
- Working one piece at a time, heavily coat the chicken in the flour mixture, pressing firmly. Dip briefly back into the buttermilk, then return to the flour mixture for a final, heavy coating to build a craggy crust. Set aside for 10 minutes before frying.
- Pour frying oil into a Dutch Oven to a depth of about 1.5 inches. Heat oil to a steady 325°F (160°C) using a deep-fry thermometer.
- Carefully lower 2 pieces of chicken into the oil (do not overcrowd). Fry for 6–8 minutes per side, maintaining the temperature near 325°F, until deep golden brown and the internal temperature reaches 165°F (74°C).
- Remove chicken and place on a wire cooling rack set over a baking sheet to drain excess oil.
- While chicken rests, gently warm the 1/2 cup reserved frying oil in a small saucepan over low heat. Whisk in the hot oil ingredients: 1/3 cup cayenne, 2 Tbsp brown sugar, 1 Tbsp smoked paprika, 1 Tbsp garlic powder, and 1 tsp salt. Simmer gently for 2 minutes, then remove from heat.
- Working quickly, brush or dip the hot chicken generously with the spicy oil mixture to glaze.
- Lightly toast the buns. Assemble the Hot Chicken Sandwich by layering the glazed thigh onto the bottom bun, topping with dill pickle slices, adding cooling slaw, and finishing with the top bun. Serve immediately.