Marinate the chicken: In a large bowl, whisk together the buttermilk, egg, salt, and pepper. Add the chicken strips, ensuring they are fully submerged. Cover the bowl with cling film and refrigerate for at least 2 hours, or up to 8 hours. The chicken will look pale and feel slightly firmer after marinating.

Prepare the dredge: In a separate, shallow dish, combine the plain flour, cornflour, smoked paprika, garlic powder, onion powder, and cayenne pepper if using. Whisk thoroughly until the spices are evenly distributed; the mixture will be a warm, speckled beige colour.

Dredge the chicken: Remove a chicken strip from the buttermilk, letting the excess drip back into the bowl. Place it into the flour mixture, pressing down firmly to coat all sides. Shake off any excess flour and set the strip on a clean plate. Repeat with all strips. You'll hear a faint rustling sound as the flour clings to the wet chicken.

Heat the oil: Pour the oil into a large, heavy-bottomed frying pan or skillet. The oil should be about 2cm deep. Heat over a medium-high flame until it reaches 175°C (350°F). If you don't have a thermometer, drop a small cube of bread into the oil; it should sizzle and turn golden brown in about 60 seconds.

Fry in batches: Carefully place 4-5 chicken strips into the hot oil, ensuring not to overcrowd the pan. Fry for 4-5 minutes per side. The chicken will hiss and bubble vigorously. Turn once using tongs. The coating will turn a deep, rich golden brown and the chicken will feel firm to the touch when cooked through. The internal temperature should reach 74°C (165°F).

Drain and rest: Using a slotted spoon or tongs, transfer the cooked strips to a wire rack set over a baking tray. This allows air to circulate, keeping the crust crisp. Do not drain on paper towels, as the steam will soften the coating. Let them rest for 2-3 minutes before serving.