First clean/wash your chicken then put the pieces in a pan. Add the ginger n garlic paste, salt and coriander paste. Add some water (about 1 cup) and boil on medium whilst covered until the chicken is almost tender. Drain and set aside. (you can use any leftover broth for soups or in the accompanying rice if you will be serving rice).
In a separate pan, pour the thin coconut milk, add salt, green chili, turmeric powder and garlic paste. Cook this milk on a gentle flame until it starts to thicken slightly, making sure to stir all the time so that the coconut milk doesn't 'break'. If it doesn't thicken, you can add a bit of corn flour. Immerse your chicken pieces into this mixture and let them boil together so that the chicken takes up the yummy coconut flavor and continues to cook plus the pieces will acquire a light covering of the sauce. I sometimes like to add some potatoes in this....just boil them separately in water and add them when you're adding the chicken pieces into the LIGHT coconut milk. This way they get enough time to get all the flavor.
Turn off the heat after a few minutes, now remove the chicken pieces and either grill them on a charcoal grill for about 5 minutes or use the coal smoking effect to give them a good bbq-type smokey flavor. Then return them back into the coconut sauce and set aside.
In a different smaller pan, pour the HEAVY coconut milk. Add juice of half a lemon and 2 tsp. of tamarind sauce/paste, salt, chili powder and a pinch of turmeric. Boil this on a low flame making sure to stir all the time until it thickens and cooks through. Adjust salt/lemon/chili. Now pour this thick sauce over the chicken pieces and mix together thoroughly. You can give the combination a quick simmer and you're done.
Serve with Mandazi or rice...enjoy!! :))