Heat the oil in a wide, shallow pan over a medium heat and spend at least 10 mins browning the chicken backbone pieces – the darker the colour, the more flavourful the gravy will be. Add the carrot trimmings, onion and onion skins, and cook for 3-4 mins over a high heat until well browned. Scatter over the sugar and cook until it starts to caramelise, then tip in the flour and cook to a sticky, light brown paste.

Splash in the soy sauce, if using, then pour in the wine or water and simmer for a few minutes until reduced and thickened. Stir in 1 litre water from the kettle, add the stock cubes and bring to a simmer. Cook gently for 40 mins, then sieve into another saucepan and season to taste. Stir in any resting juices from the chicken. Reheat when ready to serve. Can be made a day ahead and chilled, then reheated the next day.