Heat the oil in a deep fat fryer or deep, heavy-based saucepan to 180˚C (350˚F), or until a cube of bread browns in 15 seconds.
Meanwhile, lightly beat the egg white in a shallow dish and stir in the buttermilk and paprika. Season to taste then add the chicken and stir to coat. Mix the flour with the Cajun seasoning in another bowl.
Dip the pieces of chicken in the seasoned flour, then deep-fry for 3–4 minutes until golden brown. Remove with a slotted spoon and drain on kitchen paper.
Mix the mayonnaise with the chives and serve with the crispy chicken.