Prep Work

The Aromatics

• Chop up the onion fairly finely and set aside.
  1 large onion
• Pound (or use a chopper) the ginger and garlic to get a small amount of paste. Add a little water as necessary. You shouldn't need water if using a pestle and mortar. Or use a shop bought paste.
  2.5 cm ginger, 2 garlic cloves

The Spices

• Measure out all your spices, whole and ground and set them aside. Don't forget to lightly pound your black cardamoms, to help them release their aroma.
  2 black cardamoms, 1 large cinnamon stick, ½ tsp black peppercorns, 2 Tbsp Kashmiri chilli powder, 1 tsp ground ginger, ½ tsp ground coriander

The Finish

• Measure out the ratan jot or mawal, depending on which you're using.
  2 Tbsp ratan jot pieces, 1 mawal (cockscomb) flower
• If using ratan jot, place the pieces in the centre of a small square of muslin and tie into a little bundle. If you don't have muslin, don't worry, we'll strain the coloured ghee instead.

  If using mawal, set the flower aside. We'll extract its colour in water towards the end of cooking.
  1 small square sheet of muslin
• Slice the ginger into matchstick slices and set aside the fennel seeds.
  5 cm ginger, ½ tsp fennel seeds

Let's Get Cooking

• Heat 2 Tbsp of ghee in a large saucepan on medium heat.
  2-3 Tbsp ghee
• Brown the lamb shanks all over. This will take about 5 minutes, and your kitchen is going to smoke. Open the windows, turn on your extractor, and mind that smoke alarm!
  2 lamb shanks
• Take the lamb shanks out, place on a plate and set aside until needed.
• In the same pot, fry the black cardamoms, cinnamon stick and black peppercorns for 30 seconds on medium heat. Add another tablespoon of ghee if the saucepan is dry.
  2 black cardamoms, 1 large cinnamon stick, ½ tsp black peppercorns
• Tip in the onions and fry for 2 minutes on medium-low heat.
• Add the ginger-garlic paste and fry for 30 seconds.
• Add the lamb shanks back into the saucepan, along with any juices on the plate (bloody or not). Add the Kashmiri chilli powder, ground ginger, ground coriander and salt, then stir a little to coat the meat. Still on medium-low heat.
  2 Tbsp Kashmiri chilli powder, 1 tsp ground ginger, ½ tsp ground coriander, 1 tsp salt
• On the same heat, add 400 ml of water if you're using mawal, or the full 500 ml if you're using ratan jot or neither. Before the water starts to boil, slowly add the yoghurt, stirring constantly.

  I've found that the best way to prevent the yoghurt from curdling is to add a dollop (about 1 Tbsp), stir, another dollop, stir, until it's all in. If it curdles, don't worry, your curry will still be delicious.
  500 ml water
• Bring to a simmer, increasing the heat to medium if you're too impatient to wait for it to heat up. Then cover with a lid, reduce the heat right down and cook on this very low heat for 1½-2 hours, until your meat is beautifully tender.
• By the end of cooking, the meat should be almost falling off the bone, and the gravy should be rich and aromatic, but still fairly loose. We're not looking for the thick, tomato-based sauce you get in so many British curry houses. If the gravy has reduced too much, just add a splash of water.

Final Step

• If using mawal: Bring the reserved 100 ml water to a simmer in a small saucepan. Add the mawal and simmer for 1 minute, just long enough to extract its beautiful red colour. Don't leave it too long, or the colour will start turning brown. Strain the coloured water into your Rogan Josh, discarding the flower. Stir gently and simmer for another 2 minutes.

  If you're not using mawal, skip this step.
• Heat the 2 Tbsp of ghee in a small frying pan over medium-low heat.
  1 small square sheet of muslin, 2 Tbsp ghee, 2 Tbsp ratan jot pieces
• If using ratan jot: Add the prepared muslin pouch to the hot ghee and swirl it around for a minute or two, until the ghee takes on that beautiful deep red colour. Remove the pouch, gently pressing it between two spoons to release the coloured ghee, then discard it.

  No muslin? Heat the ratan jot pieces directly in the ghee, then strain through a metal sieve into a heatproof container. Return the coloured ghee to the pan, discarding the roots.

  If you're not using ratan jot, skip this step.
• Add the ginger matchsticks and fennel seeds to the hot ghee, whether coloured or not, and fry for about 30 seconds, just long enough to release their aroma. Don't let the ginger burn.
• Pour the hot, fragrant ghee all over your Rogan Josh and give everything a gentle stir. Turn off the heat and leave to rest for 5 minutes before serving. Finish with a little fresh coriander, if you like.
  2 Tbsp ghee