Heat some mustard seed oil in a pan, add the bay leaves, cinnamon, mace and cardamom pods and fry until they crackle.
Add the sliced chillies and stir-fry for a moment or two, then mix in the ground turmeric and coriander and fry for a few moments to cook the powder. Stir in the onion and ginger purées, mix well and then add enough water to make a smooth gravy.