Preheat the Oven:
Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper or aluminum foil for easy cleanup.
Prepare the Sweet Potatoes:
Peel and cube the sweet potatoes into bite-sized pieces. Place them in a mixing bowl and toss them with olive oil, chili powder, cumin, smoked paprika (if using), salt, and pepper. Make sure the sweet potatoes are evenly coated with the seasoning.
Roast the Sweet Potatoes:
Spread the seasoned sweet potatoes in a single layer on the prepared baking sheet. Roast in the preheated oven for 25-30 minutes, or until the sweet potatoes are tender and slightly caramelized. Be sure to stir halfway through for even roasting.
Prepare the Black Beans:
While the sweet potatoes are roasting, heat the black beans in a small saucepan over medium heat. Add a pinch of salt and a squeeze of lime juice (if desired) to enhance the flavor. Keep warm.
Combine and Serve:
Once the sweet potatoes are done roasting, remove them from the oven and place them in a serving dish. Add the warm black beans on top and toss gently to combine. Garnish with fresh cilantro or parsley, and a drizzle of lime juice, if desired.