Add the remaining coconut milk (cream + water) left in the first can, 2 cups of broth or water, the potatoes, star anise, sugar, and tamarind. Bring to a simmer and let cook until the potatoes are soft, 10-20 minutes depending on how large the potatoes are. Add more water or broth as needed to thin and keep the potatoes covered. You’ll end up with a thick gravy.