Pour the oil into a Dutch oven placed over low heat. Add the star anise, cinnamon sticks, cloves, mustard seeds, cardamom pods, and peppercorns. Cook the spices in the oil, stirring occasionally, for 45 minutes. Remove the spices with a slotted spoon. (Don't worry about the mustard seeds).
Add the onions, curry powder, 1/2 tsp of the salt, and sugar to the spice-perfumed oil and increase the heat to medium, stirring occasionally, until they are totally softened and caramelized. This takes at least an hour, but the slower, lower, and longer the better.
Meanwhile, add the cashews, jalapeno, tomato paste, the remaining salt, and 1 1/4 cups water to a blender, and blend until smooth and creamy. Set aside.
When the onions are caramelized, add the ginger and garlic and stir to combine until they are fragrant, about 2 minutes. Now add the chickpeas, the cashew sauce, and 3/4 cups of the chickpea cooking liquid or water. Bring to a boil, reduce to a simmer. Simmer, covered, for about 30 minutes. Serve over rice.