Take a pan & dry roast all the ingredients mentioned for Kadai Masala on low heat for 2-3 mins. Cool & rough grind the masala. Take out 4 teaspoons of this masala for the chicken. You can store the balance for future use.
Add 1 tablespoon oil to a pan on medium heat. Sauté the capsicum & onion petals in the pan for 2-3 minutes until they look blistered. Remove & set aside.
In the same pan, add the remaining 2 tablespoons of oil. Add the cumin seeds and dry red chilies. Saute for 30 seconds until cumin changes color.
Add the chopped onions. Sauté for around 7-8 mins on medium heat till the onions are light brown.
Add the ginger and garlic, and fry for 1-2 minutes till the raw smell is gone. Add the tomato purée & fry on high to medium for 2-3 minutes till the purée is cooked.
Add all the spices - turmeric, kashmiri red chili powder, coriander powder & salt. Stir and saute for 2-3 mins till the masalas are cooked & oil separates.
Add the chicken pieces and mix well. Cook the chicken pieces on medium for another 5 minutes so that they are browned & coated with the masala.
Turn the heat to low & add the whisked yogurt while stirring continuously. Cook for 2-3 minutes till the yogurt is cooked.
Add the 4 teaspoons of the Kadai Masala, stir, and saute for 2 minutes.
Add ½ cup of water, cover with a lid, and cook for 10 minutes till the chicken is tender.
Add the sautéed onion and capsicum we had set aside. Give a gentle stir.
Add garam masala, mix & cook for another minute. Turn off the heat.