Cut the chicken into fairly large pieces. I got about 6 pieces from the entire bird. The chicken can weigh anywhere between a kilo to 1.3 kilograms. If your bird is larger, adjust the spices accordingly.

Mix together sumac, hung curd, garlic paste, chili powder and salt in a bowl and rub all over the chicken, making sure that you get to all the crevices. Keep this aside for anywhere from half an hour to overnight. The longer the better.

In a oven proof roasting pan, add the chicken pieces one by one. Cook on high heat for 3 minutes on each side till the chicken gets a slight golden brown. Add the onions, garlic pods and sliced lemons to the pan. Transfer the pan to a pre-heated oven for 40-50 minutes and bake at 200 degrees celsius. In case you don't have an oven, or an oven proof roasting pan, you can also cook this on a stove (See point 5)

Remove from the oven and serve hot.

To cook on the stove: To cook the chicken on the stove, cook on high heat for 3 minutes on each side till the chicken gets a slight golden brown. Add the onions, garlic pods and sliced lemons to the pan. Reduce the heat, and cook for 20 minutes on each side, till the chicken is cooked through. Some juices will get collected in the pan while cooking. You can increase the heat, and cook till the juices evaporate, but I quite like having them in the pan.