Lamb with sweet potato & mustard dauphinoise

Lamb with sweet potato & mustard dauphinoise

A quick and delicious alternative to the traditional roast lamb, served with creamy dauphinoise flavoured with thyme and mustard.

4 out of 5 stars(1) Rate this recipe
2 of your 5 a day
  • Serves4
  • CourseMain meal
  • Prepare10 mins
  • Cook55 mins
  • Total time1 hr 5 mins

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  • 1 tbsp olive oil
  • 2 leeks, finely sliced
  • 250ml whole milk
  • 100ml double cream
  • 3 tbsp Maille Dijon Mustard
  • Few sprigs thyme, leaves only
  • 600g sweet potato, skins scrubbed then sliced into 0.3cm coins
  • 4 essential Waitrose Lamb Steaks
  • 300g spring greens (About 300g)


  1. Preheat the oven to 200˚C, gas mark 6. Heat ½ tbsp oil in a large saucepan and add the leeks, cover and sweat for 8-10 minutes, stirring occasionally until soft. Pour in the milk and cream, add the mustard, thyme leaves and sweet potatoes, then stir to coat. Season and heat until just steaming; simmer for 5 minutes.

  2. Tip the potato mixture into a small ovenproof dish (about 1-1.5 litres in volume) and arrange in even layers. Bake for 35-40 minutes until cooked through.

  3. Just before the potatoes are ready, cook the lamb. Heat the remaining ½ tbsp oil in a large frying pan. Season the steaks and fry for 3 minutes on each side, ensuring the surfaces of the meat are fully cooked. Rest for a couple of minutes, then slice and serve with the dauphinoise and steamed spring greens.

Cook’s tip

The dauphinoise would also work brilliantly alongside an Easter roast leg of lamb.


Typical values per serving when made using specific products in recipe


2,332kJ/ 559kcals



Saturated Fat












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Overall rating (4/5)

4 out of 5 stars1 rating