Deseed red chilies and soak them in 3 tbsps vinegar and 3 tbsps hot water. Set aside.

Add coriander seeds, cumin, pepper corn, mustard, cinnamon, cloves and cardamoms to a blender jar.

Make a fine powder. Then add ginger garlic and soaked red chilies.

Add the vinegar water mixture and make a smooth paste.

Next add this to the cleaned chicken along with turmeric and salt.

Marinate and rest aside for at least an hour to overnight in refrigerator to absorb the flavors.

Heat oil in a deep pot and saute the onions (optional) until golden to light brown.

Add 1 tbsp vinegar & 1 tsp sugar to the onions.

Then add the marinated chicken and saute for 3 to 5 mins on a medium heat.

Pour the tomato puree (optional) and continue to saute for another 3 to 4 mins.

If your chicken lets out lots of moisture, do not add water. Mine did not so I poured half cup hot water. If you prefer a dry curry then skip adding water. The chicken will cook in its own moisture.

Cover and simmer until the chicken cooked through & fork tender.

To check if the meat is done, prick it with a fork. The meat should fall off the bone easily.

Simmer until the gravy reaches a thick & semi dry stage. Taste and add more salt if needed.

Serve chicken vindaloo with plain rice or naan.