1 tbsp vegetable oil
1 tsp chopped fresh rosemary (or thyme)
2 carrots, peeled, chopped
½ swede, peeled, chopped
1 large parsnip, peeled, chopped
200g/7oz canned chopped tomatoes
1 litre/1¾ pints meat stock
320g/11fl oz cold leftover roast lamb, finely chopped
3-4 floury potatoes, such as Maris Piper or King Edward, peeled, chopped
1-2 tbsp butter/dairy free replacement
dash rice milk
Preheat the oven to 180C/350F/Gas 4.
Heat the oil in a heavy-based pan over a medium heat. .
Add the carrots, rosemary or thyme, swede and parsnip and continue to fry for 1-2 minutes, or until just browned.
Add the chopped tomatoes and stock, stir well and bring the mixture to a simmer.
Add the chopped lamb and continue to simmer for 20-30 minutes, or until the volume of liquid has reduced by two-thirds and the sauce has thickened.
Transfer the mixture to an ovenproof casserole dish and set aside to cool slightly.
Meanwhile, boil the potatoes in a pan of salted water for 15-20 minutes, or until tender.
Drain well, then mash with a potato masher or ricer.
Add the butter/dairy free alternative and rice milk and mash again until smooth and well combined.
Spread the mashed potatoes over the filling mixture in an even layer. Transfer the casserole to the oven and cook for 40-50 minutes, or until the potatoes are golden-brown and the filling is bubbling.