Steps: 1. To a pan, add oil; when oil heats up add mustard seeds, cumin seeds, curry leaves. 2. Add chopped onion & green chilli and stir it well. 3. Add little salt and cook till it turns light golden brown. 4. Add crushed ginger garlic or paste and cook till the raw smell goes off. 5. Add turmeric powder, chilli powder, coriander powder and then mix everything well. 6. Add chopped tomatoes and cook till its soft and mushy. 7. Add chicken masala and stir well. 8. Add little water and mix everything well for about a minute. 9. Add potato and then chicken and stir them well until it is coated with the masala. 10. Cover and cook it for about 2 - 3 minutes and then stir well. 11. Adjust salt and spices as needed and bring it to boil. 12. Cover & cook it on medium low heat for 15-20 mins. 13. Switch off the stove and add some fresh coriander leaves. 14. Top off with chopped coriander leaves before serving.