Heat 3 tbsps cooking oil in a pan and sauté 2 tsps cumin seeds, 6-7cloves, 10-12 black peppercorns, 2-3 star anise, 2 big cardamom, 4-5 small green cardamoms, 2 inches cinnamon and a couple of dry red chillies and 2 bay leaves. Sauté until fragrant. Now carefully remove the whole spices from the oil.
Add in 3 tbsps crushed garlic and ginger (I used mortar and pestle), 2 chopped/crushed green chillies and then sauté 2 cups of puréed or finely chopped onion until it turns golden brown. Add in a few tsps of water if the onion paste gets dry. We need browned not burnt onions.
Then add in 2.5 cups tomato purée, and cook them all until it releases oil and turns brownish red. Stir in 1/3 cup whisked curd and cook for another 7-8 mins (use coconut cream or thick coconut milk for vegan option). The paste would come together and start releasing oil again.
Add the dry spices – 2 tsps red chilli powder, 2.5 tsps coriander powder, salt to taste, 1.5 tsps roasted cumin powder, 1/2 tsp turmeric powder, 1 tsp garam masala (the spices are added at a lesser than required amount at this stage, more to be added later while making the dish).
Sauté it all until the spices are well blended in the paste and it looks cooked.
Store in a clean and sterilised jar for upto a week in refrigerator or freeze them for upto 3 months.