Start with the Korma paste by placing a medium frying pan on medium heat. Add the coriander and cumin seeds and toast lightly without burning to release their oil and aromas. Remove from the pan and keep aside to cool.
Use a grinder to grind the toast spices and keep aside.
Add into the bowl of a food-processor, with the metal blade attached, all of the ingredients including the toasted spices that have been grinded, and work for couple of minutes to create a smooth paste. If too thick then add some more oil.
In the same bowl of the food processor add the ginger, garlic and onions and work to a paste. Use a large high wall pan or pot, that has a lid, and add this paste along with 50ml of water on medium heat. Cook for 5’ and then add the korma paste while continuing cooking for further 3’.
Add into the pan the chicken cubes along with the broth, almonds, grapes, sugar and salt and mix well. Increase the heat, bring to a boil and simmer for 25’ with the lid on.
Remove from the heat, uncover and stir in the coconut milk, mix well and stir in the yoghurt too, remembering to be off the heat. Serve and scatter on top the fresh coriander, next or on top of basmati rice.