Cut chicken breasts into bite sized pieces and add all ingredients under "marinade" to it
Mix the chicken well with the marinade, and keep in fridge for at least 30 mins (I usually kept it overnight to marinade well)
Heat oil in a pan, and add the chopped onions, garlic, green chilies and curry leaves
When the onions are browned (5 mins), add all ingredients listed until "seasoning"
Cook for 1-2 mins, then add the chopped tomatoes and fry for another 1-2 minutes
Add the marinated chicken
Add about 1/4 cup of water (making sure not to wash off the marinade)
Close pan and cook on a low flame for about 30 minutes until chicken is cooked well
Slice the potato into quarters and add to the curry
Cook until the potatoes are done all the way. Curry is now ready to serve :)