Blend tomato and powder spices together with ginger, garlic and tomato puree.
In a pot put ghee and oil keep on flame add onions and fry till golden brown just like birista, add in chicken pieces and stir properly to make the onions mix well with chicken pieces add blended tomato, potatoes and little water then cook on medium or low flame till done, if the gravy is bit watery keep high flame to dry it up a little then can simmer to give taraa.
Garnish with chopped coriander leaves.