To make the green onion oil, combine the onion with the vegetable oil in a small pot. Heat slowly to 60°C (use a meat thermometer to check this), then remove from the heat and transfer to a blender. Blend on a high speed for 5 minutes, then strain through a fine strainer. (Any leftover onion oil will last in the fridge for a couple of weeks.)

To make the white cut chicken, remove any fat from the chicken cavity, rinse in cold water and set aside. In a heavy-based pot large enough to fit the chicken snugly, place the shaoxing, green onions, garlic, ginger and 3.5 litres water and bring to the boil.

Add the chicken to the pot and return to the boil, then reduce the heat to a high simmer. Simmer, covered, for 15 minutes. Remove from the heat and leave the chicken to steep for 20 minutes.

Carefully lift the chicken from the liquid and allow the cavity to drain. Submerge the chicken in a large pot of iced water, leaving it to cool for 15 minutes. Thoroughly drain the chicken and place it in the refrigerator to chill for a couple of hours and set the juices.

Separate the meat from the bones and discard the skin. Use your hands to shred the chicken into rough strips into a bowl. Add the ginger, a pinch of salt, onion rounds and 150ml green onion oil and toss well to combine.

Check seasoning and add more salt if necessary. Transfer to a serving dish.