Roast loin of lamb with kidneys, devilled tomatoes and colcannon

Ingredients

1 x 900g/2lb boned and rolled loin of lamb, skin removed
4 lambs' kidneys, halved and the cores snipped out with scissors
1 tsp plain flour
150ml/5fl oz good quality chicken stock
salt
freshly ground black pepper
For the colcannon
675g/1½lb Maris Piper potatoes, peeled and cut into chunks
225g/8oz curly kale or spring cabbage, thinly sliced
25g/1oz butter
1 leek or small onion, chopped
150ml/5fl oz whole milk
freshly ground white pepper
For the devilled tomatoes
¼ tsp cayenne pepper
1 tsp English mustard
½ tsp Worcestershire sauce
15g/½oz softened butter
4 vine-ripened tomatoes, cut in half
oil, for brushing

Method

1. Preheat the oven to 230C/450F/Gas 8.
2. For the colcannon, put the potatoes in a large pan of water salted with one teaspoon per 600ml (1 pint). Bring to the boil and simmer until tender.
3. Meanwhile, season the lamb with salt and pepper, put it in a roasting tin and roast for about 30 minutes, or until cooked through.
4. When it is done, remove from the oven and transfer to a board. Cover with foil and leave to rest for ten minutes.
5. While the lamb is cooking, put 1cm/½in of water into a large pan and bring to the boil. Add half a teaspoon of salt and the cabbage and cook over a vigorous heat for 4-5 minutes, until just tender, but not mushy.
6. Drain the cooked potatoes and leave the steam to die down. Drain the cabbage well.
7. Melt the butter in the pan in which you cooked the cabbage then add the leek or onion and cook gently for 7-8 minutes until very soft but not coloured.
8. Pass the potatoes through a potato ricer (if you do not have one you can use a masher) into the pan and add the cabbage, milk and white pepper to taste. Mix together well and keep hot.
9. Preheat the grill to high. For the devilled tomatoes, mix together the cayenne pepper, mustard, Worcestershire sauce, butter, quarter a teaspoon of salt and some black pepper in a small bowl.
10. Put the tomatoes on an oiled baking tray or the rack of the grill pan, brush with a little oil and season lightly with salt and pepper. Grill for 3-4 minutes until beginning to soften.
11. Season the kidneys, add them to the tray and dot the tomatoes with some of the devilled butter. Grill for a further 4-5 minutes until the kidneys are completely cooked through.
12. Meanwhile, pour off any excess fat left in the roasting tin, place it over a medium-high heat and stir in the flour.
13. Add the stock and boil rapidly for a minute or two until reduced to a well-flavoured gravy, scraping the base of the tin to release all the caramelised juices. Strain into a small pan, adjust the seasoning and keep warm.
14. Carve the lamb across into thin slices. Spoon the colcannon on to warmed plates and place the slices of lamb alongside. Add the kidneys and devilled tomatoes, pour some gravy over the lamb and serve.