1. Peel the potatoes, quarter and soak in cold water for at least 15 minutes. Place soaked potatoes in a large saucepan and cover with more cold water. Bring the water to the boil, then boil for 15 minutes, until a sharp knife penetrates the potatoes easily.

2. Drain well and return to a low heat for five minutes to remove any remaining moisture. Keeping the potatoes over the heat, mash until all lumps are removed.

Add the butter, milk, yoghurt and salt and beat with a wooden spoon until the mashed potatoes are light and fluffy. Keep warm until ready to serve.

3. For the chicken gravy, place the chicken roasting pan over medium heat and scatter the flour into the pan, scraping it around until it forms a brown paste and starts to fry.

4. Add the Vegemite (if using) and stir to combine. Add the white wine and chicken stock a little at a time, continuing to stir until a gravy the consistency of pouring cream is formed. Add any juices collected from the resting chicken.

5. Remove from the heat and strain the gravy into a jug, pressing the vegetables to extract any last juices. Keep warm until ready to serve.

6. Serve the potatoes in a bowl with some of the gravy poured over the top. Finish by stirring the white wine vinegar into the remaining gravy and serve with the chicken and peas.