Preheat your oven to 400°F (200°C).
- Pierce the sweet potatoes with a fork a few times and place them on a baking sheet. Roast in the preheated oven for 40-45 minutes, or until tender when pierced with a fork.
- While the sweet potatoes are baking, heat the olive oil in a large skillet over medium heat. Add the onion and garlic and cook for 3-4 minutes until softened.
- Add the ground turkey to the skillet, breaking it apart with a spatula as it cooks. Cook until the turkey is browned and fully cooked, about 5-7 minutes.
- Stir in the cumin, chili powder, paprika, cayenne pepper (if using), salt, and pepper. Add the corn and black beans and cook for another 2-3 minutes, until heated through.
- Once the sweet potatoes are done, remove them from the oven and let them cool slightly. Cut a slit down the center of each potato and gently fluff the inside with a fork.
- Spoon the turkey mixture into each sweet potato, filling them generously.
- Top with shredded cheddar cheese, if desired, and return to the oven for an additional 5 minutes to melt the cheese.
- Serve the stuffed sweet potatoes with a sprinkle of fresh cilantro, a dollop of sour cream or Greek yogurt, and lime wedges on the side.