Heat the olive oil in a large pot over medium heat. Add the onion and cook for 3 minutes until it softens.
Stir in the garlic and cook for 1 minute until fragrant.
Add the sweet potatoes, cumin, chili powder, and smoked paprika. Stir to coat the potatoes with the spices.
Pour in the vegetable broth and diced tomatoes. Bring the mixture to a boil.
Reduce the heat to a simmer and cook for 15 minutes until the sweet potatoes are tender.
Stir in the black beans and cook for 5 more minutes to heat them through.
Season with salt and black pepper. Serve with chopped cilantro and lime wedges on the side.