In a blender or food processor, combine soaked chili peppers, salt, lemongrass, turmeric, galangal, shallots, garlic, shrimp paste, coriander seeds, cumin seeds, white peppercorns, and curry powder. Blend until the mixture forms a paste that still has a small amount of texture, pausing to scrape down the sides as needed. (Note: if the mixture does not blend easily, add water a bit at a time, as needed, to help it blend.)