In a large heavy pot, heat the oil over medium heat, then add the onions, ginger, garlic, coriander, and cumin and cook, stirring, until the onions are soft and translucent, about 5 minutes. Add the tomatoes, bell pepper, potatoes, broth, honey, and hot pepper. Bring to a boil, reduce the heat to low, and simmer, covered, for 30 minutes. Remove the hot pepper. Using a blender or food processor, puree the soup in batches. Return it to the pot, stir in the coconut milk and salt, then heat just to a simmer. Serve, garnished with dollop of yogurt, cashews, and cilantro.