Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
   1      teaspoon      coriander seeds
   1      teaspoon      cumin seeds
   4                    green cardamom pods
   1      2 inch long   cassia bark or cinnamon sick -- broken up
   4      long          dried red chillies
     1/2  teaspoon      black peppercorns
   2                    bayleaves
     1/2  teaspoon      fenugreek seeds
     1/2  teaspoon      black mustard seeds
   1      tablespoon    ginger paste
   1      tablespoon    garlic paste
   1      kilogram      skinned chicken thighs
  50      grams         ghee or unsalted butter
   1      teaspoon      salt or to taste
 125      milliliter    warm water
                        ***LENTILS***
  75      grams         toor dhal or yellow split peas -- washed and soaked
                        -- for 30 minutes
  75      grams         masoor dhal -- washed and soaked
                        -- for 30 minutes
   4      tablespoons   sunflower or soya oil
   1      large         onion -- finely chopped
   1      teaspoon      ground turmeric
   1      teaspoon      garam masala
 600      milliliter    warm water
   1      teaspoon      salt or to taste
   1      teaspoon      tamarind concentrate or 1 1/2tbsp lemon
                        -- juice
   2      tablespoons   chopped coriander leaves

Preparation:

Grind the ingredients until fine in a coffee mill. Add 75ml water to the ground spices and make a paste, then mix with the ginger and garlic. Rub this mixture into the chicken making sure that the spices coat them thoroughly. Cover and leave to marinate in a cool place for 4-6 hours or overnight in the fridge. Bring back to room temperature before cooking. Melt the ghee or butter over a medium heat and fry the chicken, stirring frequently, for 6-8 minutes. Add the water and salt, allow to bubble gently, then cover the pan and reduce the heat to low. Cook for 15-20 minutes, stirring occasionally. Drain the lentils and mix them together. Heat the oil over a medium heat and fry the onions for 5 minutes, stirring frequently. Add the turmeric and garam masala, soak for 30 seconds. then add the lentils. Reduce the heat to low and fry the lentils for 4-5 minutes, stirring frequently, then add the water. Bring to the boil, cover the pan and reduce the heat to low. Simmer for 30 minutes or until the lentils are soft. Stir occasionally. Stir in the salt, remove from the heat and cool. Puree the lentils in a blender and pour over the chicken. Cook on a medium heat until it begins to bubble. Reduce the heat to low, cover the pan and cook for 20-25 minutes. During the last 10-15 minutes, stir frequently to ensure that the thickened sauce does not stick to the pan. Add the tamarind and stir until dissolved. Cook for 2-3 minutes, then stir in half the coriander leaves. If using lemon juice, add it along with the coriander leaves. Remove from the heat and serve garnished with the remaining coriander leaves.