Cut the chicken into 1.25 cm / 1/2" cubes. Keep the pieces even so they fry quickly and finish at the same time.

Whisk the buttermilk, salt, and egg in a bowl, then coat the chicken in the mixture and refrigerate for 1 hour. The chicken should be fully coated, and do not marinate it for longer than 24 hours.

Combine the flour, corn flour / cornstarch, and all of the herbs and spices in a large bowl. Break up any visible herb clumps so the seasoning distributes evenly.

Drizzle 3 tablespoons of the marinade over the flour mixture and rub it in with your fingertips. The mixture should develop many small, uneven clumps rather than staying powdery smooth.

Choose a heavy-based 20 cm / 8" saucepan or small pot, or use a 24 cm / 9.5" deep skillet only if you are comfortable frying in a wider pan. A sturdy pan holds heat more steadily and gives you better control over the oil.

Heat the oven to 50°C/125°F for holding finished batches. The low heat keeps the chicken warm without aggressively browning the crust further.

Use one hand to lift chicken from the marinade and scatter it over the flour mixture, then use a spoon or dry hand to cover it with flour. Keeping the wet and dry jobs separate prevents thick doughy buildup on your fingers.

Pull apart the chicken pieces, press the clumpy flour onto every surface, and shake away loose excess before arranging the pieces on a tray. Each piece should look irregularly coated, with small crags attached rather than a smooth blanket of flour.

Just before each batch goes into the oil, toss those pieces lightly in the flour left on the tray. Check that no pieces are stuck together, since joined pieces cook unevenly.

Line a tray with paper towels and keep the oven at 50°C/125°F. Have the tray ready before frying so the cooked chicken can drain without delay.

Pour oil into the pot until it reaches 2.5 cm / 1" deep and heat it over medium-high heat to 180°C/350°F. The oil should shimmer and give a gentle, steady bubble when the first chicken pieces enter.

Shake a small batch in a large-hole spider skimmer to remove loose flour, then lower it carefully into the oil and fry for 2 - 2.5 minutes. Separate any pieces that touch, and look for a deep golden-tan crust and buoyant pieces floating near the surface.

Lift the chicken out with the spider skimmer and spread it across the lined tray before moving it to the warm oven. Check a thick piece with a thermometer, since poultry should reach 165°F before serving.

Repeat with the remaining chicken, then serve while the coating is hot and crisp. The finished bites should crackle lightly when broken open and reveal juicy chicken inside.