1Add few spoons of water, add all the ingredients listed for the paste and grind them into a fine paste.
1Heat oil in a cooking vessel, add mustard seeds and as they spit, add ginger garlic paste and sauté for about 3 mts.
2Add coriander powder, turmeric powder and salt. Mix well .
3Add the chicken pieces and fry until they are vaguely browned. Take away the chicken pieces and keep aside.
4In the same pan drizzle some more oil and fry the onions for 5-10 miinutes until golden.
5Add ground masala paste and saute for 2 minutes.
6Add the vinegar and jaggery mixture and combine along with the chicken and its marinade and stir-fry for 5 minutes to seal the meat.
7Add 1 1/2 cups of water to browned chicken pieces and add in the tomatoes.
8Cover and simmer for 30 minutes. Remove the lid for the last 10 minutes of cooking. Cook till the chicken turns soft and it forms a thick gravy.
9Meanwhile, cook the potatoes in boiling water for 10-15 minutes until tender. Drain.
10Add the potatoes to the cooked vindaloo and serve hot.