Method

1. Preheat oven to 180ºC. Put potatoes and salt in a large pan and cover with cold water by 10cm. Cook over a high heat for 30 minutes or until soft.
2. Meanwhile, heat oil in a large pan over a high heat, add vegetables, then stir-fry for 5 minutes. Season with salt and pepper, then stir-fry for a further 5 minutes. Sprinkle flour over top and cook, stirring, for 1 minute.
3. Add mince, stirring well to break up any lumps, then cook, stirring regularly, for 5 minutes. Stir in tomato paste, stock and wine, then bring to the boil. Reduce heat to medium and simmer for 5 minutes. Whisk in gravy powder and parsley. Transfer mixture to a large, ovenproof pan or dish.
4. Drain potatoes and mash well. Beat in cream and butter until smooth and season with salt and pepper. Evenly spoon potato over lamb mixture, then bake for 30 minutes. Sprinkle over cheese and bake for 15 minutes. Cool for 5 minutes before serving.