Shepherd’s pie with lamb’s liver

Heat 1 tbsp oil in a wide, lidded frying pan or flameproof casserole dish. Fry the mince for 10 mins or until well browned. While it cooks, remove large tubes, stringy bits and membrane from the liver, and discard, then finely chop the liver.

Add the liver to the mince and cook for a few mins until it changes colour. Tip the mince and liver into a bowl, deglaze the pan using a splash of the stock, then pour the liquid on top of the mince and liver mixture. Wipe out the pan.

Heat the rest of the oil. Add the vegetables and herbs, season and soften for 10 mins. Stir in the purée, Worcestershire sauce, mince, liver and stock. Cover and simmer for 1 1⁄2 hrs until the sauce is rich and the meat tender. After 45 mins, stir it and add a splash of water if at all dry. If any bits of liver look prominent, mash them into the sauce.

Start the mash topping with 30 mins cooking time to go. Heat oven to 190C/170C fan/gas 5. Boil the potatoes until tender, then drain. Warm 150ml of milk in the potato pan, then add the drained potatoes and the butter. Mash until smooth, adding more milk if needed. Season generously and stir through most of the cheese and all the parsley.

When the mince and liver is ready, transfer it to a deep baking dish. Top with the mash, smoothing it to the edges of the dish, then scallop the top with a knife or leave it rough. Scatter with the rest of the cheese and bake for 45 mins until golden and bubbling. Let stand for 5 mins, then serve with seasonal vegetables and an extra dash of Worcestershire sauce.