Dry roast the karahi masala spices in a pan for about a minute or two until fragrant.Grind to a coarse powder in a food processor.Keep aside.
Heat a karahi or wok, add oil.Once heated add the sliced onions. Saute until slightly golden.
Add the ginger and garlic and saute for abt a minute.
Add tomato paste,turmeric,red chili powder and half of the karahi spice and mix well on medium low heat.
Add the pureed tomatoes and let the paste cook well and oil separates from the sides.
Add the chicken followed by the rest of the spice powder.Add water and salt.
Mix well,bring to a boil, cover and cook on medium until the chicken is fully cooked.
Serve hot with paratha or roti.