Preheat the oven to 200℃

Peel and chop the sweet potatoes, cover with water then bring to the boil. Simmer until they are tender.

Drain them and leave to steam dry.

Meanwhile, in a large pan, add a little bit of oil and cook the onion, carrot and celery for about five minutes over a medium-high heat until it starts to soften.

Add the garlic and cook for one more minute before adding in the minced lamb. Use a wooden spoon or a spatula to break up the lamb into smaller chunks.

Cook the lamb, stirring occasionally until it is browned all over.

Pour in the lamb stock, worcestershire sauce and then add the tomato pureé. Stir well and bring to a simmer, cook for about five minutes.

Taste for seasoning. Mix the cornflour with 2 tbsps of cold water, then pour it into the lamb, stir it well until it thickens slightly.

Add the peas, stir well then transfer it to an oven proof dish. Use one that is deep enough to leave quote a bit of space at the top.

Mash the sweet potatoes, then stir in the salt and paprika. Spoon it over the top of the meat, then smooth it over so it completely covers the whole thing.

Use a fork to rough it up a bit, then pop it into the oven for about 20 minutes.

Enjoy!