Cut the cauliflower into small bite size pieces. Put the cauliflower pieces in a bowl of hot boiling water, also add 1 tbsp of vinegar to it. Let it stand for few minutes and then throw away the water. Rinse the vegetable in cold water.
Preheat the oven to 250 degrees C. Marinate the cauliflower pieces in 1 tbsp yogurt and 1 tbsp of tikka masala powder for 15 minutes. Spread the marinated pieces on a baking tray and drizzle some cooking oil over it.
Grill for about 20 minutes or until the cauliflower has turned crispy and golden. Remove from oven and set aside.
Heat 4 tbsp of cooking oil in a saucepan, and add all the whole spices. Also add 1 tbsp of coriander powder and 1 tsp of garam masala powder and fry for few seconds.
Add 1 tbsp grated garlic and 1 tbsp grated ginger and fry for half a minute.
Then add 1 chopped onion and saute until soft and light golden. To that add 1 chopped tomato, few mint leaves and a green chili.
Fry for a minute till everything is soft and well combined.
Now add 2 tbsp or little less of tomato puree (this is added to give nice color and texture to the gravy).
Add remaining spices like 1 tbsp red chili powder, 1 tbsp tikka masala powder, 2 tbsp of kasoori methi and 1/2 cup whisked yogurt. (Salt will be added later)
Stir well and let the gravy cook well on low heat with the lid on for at least 10 minutes.
Now add the 1/2 cup fresh cream and stir well. Also add the chopped bell peppers green and red. Place the lid and cook for 1 minute. Do not over cook the bell peppers, let them be raw and crunchy.
Add the grilled cauliflower pieces to the gravy and cook for another 2 to 3 minutes. Taste and add salt only if needed.
Garnish with chopped coriander leaves and serve hot as a side dish or with roti or naan.