Heat the oil in a nonstick pan. Add the cardamom, cloves, cinnamon and bay leaves. Stir until he cardamom begins to turn lightly golden, about two minutes.
Add the cumin and coriander seeds and stir-fry for a few more minutes until the coriander starts to darken slightly.
Add the onions, ginger, garlic, a pinch of salt, and sugar. Stir-fry over medium heat until the onions start to turn brown.
Add the kasoori methi, tomato paste and tomatoes and mix well. Add 1/4 cup of water, cover, and let the mixture cook about 15 minutes or until the tomatoes are really mushy and most of the water has evaporated.
Let the mixture cool, then transfer to a blender along with the soaked cashews.
Blend into a smooth paste, adding a little water, a tablespoon at a time, if necessary to keep the blades moving.
Scrape into an airtight jar and store in the refrigerator if you plan to use within a week, or in the freezer if you want to keep it for longer. Thaw out before using.
Next, stay tuned for a curry using this tikka masala curry paste.