Instructions

• Make lamb mince filling:
• 01 Heat 1 tbsp sunflower oil in a medium saucepan or large, deep frying pan. Add chopped onion soften. 
When soft turn up the heat and add lamb mince and brown. Add carrots, mushrooms and tomato purée and a large splash of Worcestershire sauce, then fry for a few mins.
Add beef stock, bay leaf and bring to a simmer, cover and cook for 40 mins.
• Make potato mash:
• 02 Boil the potatoes in salted water until tender. Drain. Using the same saucepan dry the potatoes over heat (allow to steam for a few minutes), remove from heat and mash smooth. Push potato puree to one side of the pan, add milk and butter. Heat both until milk simmering and butter melted. Remove pan from the heat and slowly mix all together to form a smooth purée. Taste and season if necessary.
• Assemble:
• 03 Pour lamb mince filling into an ovenproof dish. Top with the creamy mashed potato and with a fork rough the top. Scatter on the top with extra cubes of butter which will melt during cooking - see image #2.
• Bake:
• 04 Bake in a hot oven for 40 minutes or so until the top is starting to colour and the mince is bubbling through at the edges. 
• Serve:
• 05 Take to the table hot and enjoy with your favourite cooked vegetable.