Place the chicken into a bowl and add the soy sauce, sake and rice wine vinegar. Mix well and allow the chicken to marinate for ideally 30 minutes to enhance the flavour.

Heat sunflower oil in a deep pan or fryer to 175–180°C. Test the oil by sprinkling a small amount of cornflour on the surface—if it sizzles, the oil is ready.

Take a piece of chicken and coat it in the cornflour, before placing into the pan. Repeat in batches, turning as needed, until they are golden and crispy. Remove and drain on paper towel.

While the chicken is frying, prepare the dipping sauce by combining Kewpie mayonnaise with sriracha in a small bowl, stirring until smooth and evenly mixed.

Serve the freshly fried chicken immediately, accompanied by the spicy mayonnaise on the side for dipping.