Marinate the chicken pieces with ginger garlic paste, Salt, Red chili powder, Turmeric Powder, Cumin Powder, Sugar, and Dry Mango Powder. Rub everything well and leave it in the refrigerator for 15 minutes.
Add Oil to a pan. Add the nigella seeds. Once they crackle, add the curry leaves and dry red chilies. Saute for 2 minutes and add the Onions.
Once the onions turn transparent, add the green chilies.
Add the marinated chicken pieces with all the juice from the marination. Cook for 10 minutes till the color of the chicken changes a little.
Add the tomato puree. Cook for 10 minutes, till the puree, starts boiling.
Add the Methi leaves. Mix well.
Add the Yogurt. Cover and cook on a medium flame for 10-15 minutes till the gravy thickens and grows a little darker.
Oil should separate in the end. If it doesn’t, then the curry needs to be cooked a little more.