Roast Lamb with Rosemary and Sage Pesto with Rosemary and Lemon Roast Potatoes

A classic; roast lamb with beautiful accompanying flavours.


  • 1 joint of lamb
  • 2 large sprigs of rosemary
  • 1 bunch of chopped rosemary
  • olive oil
  • 1 small bunch of sage
  • 30 g pine nuts
  • 75 g parmesan (grated)
  • 1 lemon
  • sea-salt
  • 3 cloves of garlic
  • 1 kg new potatoes


  1. Make a rosemary-infused oil by gently heating enough oil to fill a bottle (75cl): add the sprigs of rosemary to the bottle and pour the cooled oil in. Seal and keep in a cool place. Do this well ahead of time if possible.
  2. Make incisions all over the lamb and insert slivers of garlic into the flesh. Rub all over with olive oil, grate a little lemon zest directly onto it and sprinkle with sea-salt. Heat the oven to 180°C.
  3. Colour the lamb all over by gently searing it in a pan with a little olive oil. Place in the oven for roughly 60 minutes for a 2.5kg joint (allow for resting time before carving but by all means leave the lamb in the oven for longer if you require the meat more cooked).
  4. Make the pesto by combining the sage, pine kernels and parmesan in a blender, then slowly add the rosemary oil until a pesto-like consistency is achieved.
  5. Blanch the potatoes then prepare for the oven. Roll them in a little olive oil, add the juice of the lemon and sprinkle with sea-salt and the chopped rosemary. Add to the oven 30 minutes before the lamb is cooked and turn frequently until golden all over.
  6. To serve, carve the lamb that has been resting for approximately 12-15 minutes and plate with the roast rosemary potatoes. A ‘jus’ can be made by recovering the meat juices with a little warm water and/or white wine. Serve with this jus, if desired and of course the rosemary pesto to one side.


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