Brine the chicken. Whisk the buttermilk, hot sauce, salt, pepper, and garlic powder in a large bowl. Submerge the chicken thighs completely, cover, and refrigerate for at least 4 hours, ideally overnight (up to 24 hours).

Set up your dredging station. In a wide shallow bowl, whisk together the flour, cornstarch, paprika, garlic powder, onion powder, cayenne, salt, and pepper. The cornstarch is key — it fries up lighter and crunchier than flour alone.

Double dredge for maximum crunch. Pull a thigh from the brine, letting excess drip off. Coat in the flour mixture, pressing firmly. Dip it back into the brine briefly, then dredge a second time. Rest the coated thighs on a wire rack for 10–15 minutes.

Fry at 350°F. Pour oil into a heavy skillet or Dutch oven to 1½ inches deep and heat to 350°F. Fry 2 thighs at a time for 6–8 minutes per side, until deep golden brown and the internal temperature hits 165°F. Drain on a wire rack.

Make the signature hot oil. Carefully ladle ½ cup of the hot frying oil into a heatproof bowl. Whisk in the cayenne, brown sugar, paprika, and garlic powder until it forms a vivid red, fragrant oil.

Brush generously. Brush the hot oil all over each fried thigh — front, back, edges.

Assemble the sandwich. Toast buttered brioche buns until golden. Pile on coleslaw, add the hot chicken, top with dill pickle chips, and crown with the top bun. Serve immediately.