An unbeatable shoulder-of-lamb shepherd’s pie recipe ideal for Easter, as dreamed up by the chefs at Fortnum & Mason

If you're looking for a dish that mixes show-stopper with comfort food, this is just ideal.

The key to the recipe is using shoulder of lamb, slow-braised on the bone — ‘for serious depth and heft’, say Fortnum & Mason’s chefs — while serving it up with mash makes this an ideal late-winter/early-spring classic.

‘Pick the meat while still warm,’ the chefs suggest. ‘It makes the job easier. And baking the potatoes first will give you a drier, fluffier mash than the boiled equivalent.’

Ingredients for overnight shoulder-of-lamb shepherd’s pie

Serves 8

  • 1 shoulder of lamb on the bone
  • 2 carrots, cut into 1cm dice
  • 1 celery stalk, cut into 1cm dice
  • 8 garlic cloves, finely chopped
  • A sprig of rosemary, leaves finely chopped
  • Leaves from 4 sprigs of thyme
  • 2-3 tablespoons Worcestershire sauce, to taste
  • 3 tablespoons tomato ketchup
  • 500ml chicken stock
  • A handful of frozen peas
  • Salt and freshly ground pepper

For the duchesse potato topping

  • 6 large baking potatoes (about 2kg)
  • 200ml double cream
  • 120g unsalted butter
  • 6 egg yolks

Method

Season the lamb shoulder well and put it on a wire rack in a roasting tray. Cover the tray loosely with foil, place in the oven at 120oC/Gas Mark ½ and slow-roast for about 8 hours – at Fortnum’s they normally put it in at the end of a shift so it is ready for the next morning. Pick the meat out, removing all fat and skin – it is a lot easier to do this while it is still warm. Shred it into decent-sized pieces.

Heat a spoonful of lamb fat from the roasting tray in a large pan, add the carrots, celery and onion and cook gently until soft. Stir in the garlic and herbs and cook for a couple of minutes longer. Add the Worcestershire sauce, tomato ketchup and the lamb and mix well. Pour in the sock and simmer for 15-20 minutes, until it has reduced but the mixture is still moist. Check the seasoning.

To make the topping, wrap the potatoes in foil and bake at 200oC/Gas Mark 6 for about an hour, until tender. Leave until cool enough to handle, then cut them in half, scoop out the flesh and push it through a potato ricer or a sieve into a bowl. Bring the double cream and butter to the boil in a pan and beat them into the potato. Season well, then mix in the egg yolks. Put the mixture into a piping bag fitted with a star nozzle.

Put the lamb mixture into a large pie dish, pressing it right down. Scatter the frozen peas over, then pipe the duchesse mix on top, covering the filling completely. Place in an oven heated to 180oC/Gas Mark 4 for about 20 minutes, until piping hot and golden brown.