Heat oil in a large pot. Add the whole spices, onions, ginger & garlic.
Saute/fry them on a medium heat until transparent. For deeper flavors saute them until light golden brown on a low flame,
Stir in red chilli powder, coriander powder, garam masala, cumin powder & fennel powder.
Stir in the tomatoes, carrots and bell peppers. Stir fry for 2 to 3 mins on a medium heat.
Pour 1½ cups water or broth. Bring it to a rolling boil.
Cover and cook on a medium heat until all the veggies are mushy. Add more water/broth at this stage, as you cook.
Add salt and sugar when they are soft.
Cool this and remove the bay leaf, black cardamom, star anise and cinnamon. Blend to a smooth thick sauce, adding more liquid as required. To use the sauce as a dip or on pizza, in sandwiches and marinades, keep the consistency thick.
Taste test and more garam masala if you want. Your curry sauce is ready. Transfer to a glass freezer safe containers.
Vegetable Curries: Grill, roast or stir fry your favorite veggies until tender. Season with salt and spice. Add the required amount of sauce and simmer for 2 to 3 mins. For a loose consistency, add some broth, coconut milk or cashew cream or heavy cream and bring it to a gentle boil.
Meat Curries: Marinate prawns, chicken or lamb with spices, yogurt/buttermilk & herbs or with the curry sauce itself. Grill, roast or stir fry them until tender and add to the hot curry sauce. If the sauce is too thick, add some broth/coconut milk or cashew milk. Simmer for a few minutes until the flavors are absorbed.
Perform the steps till you saute the onions on a SAUTE mode. Turn off the IP. Stir in all the ground spices, followed by the veggies and 1½ cups water.
Pressure cook on high pressure for 16 minutes. Let pressure drop naturally, discard bay leaf, cinnamon, star anise and black cardamom. Blend the ingredients & pour back to the IP.
Add sugar (optional) and salt. Taste test and add more garam masala if required. If the sauce is too thick you may add little water. Cook on a saute mode until you see traces of oil/fats on the sauce and the curry sauce turns thick. This takes about 5 minutes.