Add the diced sweet potatoes, black beans, onion, and garlic to the slow cooker.
Pour in the diced tomatoes with their juice and the vegetable broth.
Sprinkle the chili powder, cumin, smoked paprika, salt, and black pepper over the top.
Stir everything together until the spices are evenly distributed.
Cover and cook on low for 6 to 7 hours or on high for 3 to 4 hours, until the sweet potatoes are tender.
Stir once more before serving to check the consistency.