Shepherd’s Pie

Peel the carrots, turnips and celeriac and dice roughly into 2cm cubes. Peel and thinly slice the onions.

Make the mash with the potatoes, milk and butter. Peel the potatoes and cut into chunks. Place the chunks in a saucepan of cold salted water, cover and bring to the boil, then boil gently for about 20 minutes until tender. Bring the milk and butter just to the boil in a separate saucepan. Drain the potatoes in a colander, then stand the colander over the saucepan for a few minutes so the potatoes steam in their own heat. Now mash the potatoes with a masher, or put through a potato ricer or Mouli, then fold in the hot butter and milk and beat well. Check the seasoning and set aside at room temperature until ready to use.

Preheat the oven to 170°C/150°C fan/gas 3.

Heat a splash of olive oil in a large flameproof casserole, season the shoulder of lamb with salt and pepper and brown slowly over a medium heat in the hot oil. Lift the shoulder out of the pan, then add the mince and season with salt and pepper. Cook over a high heat until well coloured, then remove and set side to drain in a colander placed over a bowl.

Put all the root vegetables in the pan and brown them over a high heat, then remove and set aside to drain.

Add the onions to the same pan (you may need to add a touch more olive oil at this point) and brown them lightly, then add the vinegar and reduce in volume by one-third.

Put the mince back into the pan and mix with the onions, then place the shoulder on top with the whole heads of garlic. Pour in the stock, add the thyme, rosemary and bay, and cover with a ‘lid’ of parchment paper.

Place the pan in the oven and cook for 1 and a half hours, then spoon the juices over the shoulder and check that the meat is coming away from the bone with ease – it should then need a further 30 minutes to cook through completely. Remove the pan from the oven and leave until the meat is cool enough to handle.

Increase the oven temperature to 220°C/200°C fan/gas 7.

Take the shoulder out of the pan and scrape all the meat into a bowl, fat and all. Discard any sinew and bones. Lift the garlic out of the pan and squeeze the flesh into the meat in the bowl. Discard the garlic skins together with the thyme, rosemary and bay. Now add the mince, cooking juices and onions to the bowl and stir well to mix.

Place the meat mixture in a casserole or baking dish to finish the pie. Place the vegetables on top and cover with the mash. Use a palette knife to smooth the mash down, then make light indents in the top with the side of the knife.

Place the pie in the oven and cook for 15 minutes, or until the mash is golden brown.