Dry roast the spices under Masala- Coriander Seeds,Chillies,Turmeric,Cumin,peppercorns,Cinnamon Stick,Cloves,Cardamom & Saunf.
Once they cool down, Powder them in a food processor.
In a Pan, Add the oil.
When the oil is sufficiently hot add the mustard seeds.Once they start to splutter add ginger ,garlic & curry leaves.
Add and sauté the finely sliced shallots till they are brown.Now either move them to the side or remove them from the pan.
Add the chicken and let it brown without moving too often.Roast it for 10-15 minutes to get a good caramalised on all sides.If it's getting too dry add a tablespoon of water.
Add and mix back the onions. Add the powdered spices. Spoon in the vinegar along with ½ cup of water. Add salt to taste.
Cover and cook for 20 minutes on medium flame.
Garnish with coriander leaves and serve with Dal and Rice or Chapattis.