For the Massaman paste:
1. Using a frying pan, dry fry the coriander seeds, cumin, cardamom, cinnamon, cloves, peppercorns, chillies and salt until the chillies become brown in colour.
2. Remove from the heat, and transfer into either a coffee grinder or a pestle and mortar. Pound or blend until you achieve a fine powder and keep to one side.
3. Wrap some shrimp paste in foil and heat in a pan a minute on either side. This mellows out the intense flavour of the shrimp paste. Remove from heat and discard the foil, keeping the shrimp paste and set aside.
4. Heat the oil in a pan, and sauté the shallots, garlic, galangal, Kaffir lime leaves until the shallots and garlic soften and become fragrant.
5. Add the shrimp paste and continue to stir fry for a couple of minutes until the mixture has browned slightly. Remove from the heat and allow to cool.
5. Using either a pestle and mortar or a blender, blend the shallot and garlic mixture along with the ground spices, nutmeg, coriander stalks and lime zest into a smooth paste.
This will keep for up to 5 days in an air-tight container in the refrigerator.
For the Lamb Shank Massaman:
1. Place the oil in a large pan and sear the lamb shanks until golden. Remove from the pan and rest.
2. Mix together the Massaman paste, coconut milk, water, palm sugar, tamarind juice and fish sauce.
3. Put the lamb shanks in a pan and coat with the mixture. Add the cardamom pods and cinnamon sticks.
4. Put in the oven on 170°C and cook for 3 hours.
5. Add the potatoes and cook for a further 25-30 minutes.
6. Leave to rest and garnish with fried onions and coriander.