Prepare the black beans according to the package directions, adding two tablespoons of olive oil/coconut fat while simmering. Saute the onion, pepper, and sweet potato in the remaining oil or fat until onion is a little golden. Add diced tomatoes, lime juice and just enough water to simmer until the sweet potato is tender. Combine black beans with vegetables. Ten minutes before serving, add the mango, hot sauce, salt and half of the cilantro and simmer. Serve with the remaining cilantro for garnish.