Instructions

To start on the topping, chop the sweet potato into large chunks. Add to a pot of boiling water and cook for 25 minutes or the potato is cooked through.

Meanwhile, heat the oil in a large frying pan over medium heat. Add the lamb mince and cook, stirring until browned. Pour off the excess fat.

Add the vegetables and spinach. Stir until wilted and mixed through.

Add the Worcestershire sauce, tomato paste and beef stock. Bring to the boil, reduce heat to low and cook for 25-30 minutes, stirring occasionally.

When the meat has finished cooking, pour it into an overproof dish.

Drain the potatoes and mash together with the milk and butter. Spread over the top of the meat in the dish and then sprinkle with cheese.

Bake in an oven preheated to 180C for 30-40 minutes or until the cheese has melted and is golden brown.