Shepherd’s Pie

Heat a large heavy-based saucepan over medium–high heat and add a splash of oil. Add the onion, carrot and celery, if using, and cook for 5–6 minutes, stirring often. Add the lamb and cook for a further 5–6 minutes, stirring often, until brown. Add the cumin, Worcestershire sauce, tomatoes and enough stock to cover. Bring to the boil and season with the salt and pepper. Cook for 30 minutes, stirring often. Check the seasoning and adjust to your liking.
Meanwhile, place the potatoes in a large saucepan and cover with cold water. Bring to the boil then reduce the heat and cook for 12–15 minutes, until tender. Allow to cool.
When ready to cook the shepherd’s pie, preheat the oven to 180°C.
Spoon the lamb into a deep casserole dish. Slice the potatoes and arrange in an overlapping layer over the top of the lamb mixture. Season with salt and pepper and brush with the melted butter. Bake for 20–30 minutes, or until the surface is golden brown and crisp.