Mix the olive oil, salt, pepper, cumin, turmeric, ginger, paprika and cayenne together in a large bowl, and toss the sweet potatoes in this mixture.
Add the cooked sweet potatoes. Season to taste with additional salt and pepper. Mix gently but well and serve garnished with additional chopped cilantro.
Dried vs Canned Black Beans: Dried black beans need to be soaked overnight and then cooked. The length of time needed to prepare them is their biggest drawback when it comes to comparing them to canned beans. But from a nutrition and sodium perspective, dried, soaked home-cooked beans are definitely better and richer in nutrients. If you do go for the canned variety, which can be quite high in sodium, look for low-sodium brands and rinse the beans thoroughly.