Heat oil in a pan or kadai and add the chopped onions.
Fry on high heat for 10 mins till brown in colour.
Add the crushed ginger and garlic and fry on medium heat for 2 mins.
Add the chopped tomatoes and green chillies and fry on medium heat for 2 mins.
Add the turmeric powder and mix & fry on medium heat for around 3 mins till tomatoes are soft.
Now add the chicken pieces and fry on high heat for 2-3 mins till the chicken pieces are browned.
Add the readymade chicken masala, red Chilli powder and salt, mix and bhunno on high heat for 5 mins. Continue to fry on medium heat for another 5 mins.
Now add 200 ml water and cook on low heat for around 20 mins till the chicken pieces are tender and oil separates.