Preheat oven to 400°F.
Place a 12-inch cast iron skillet over medium-high heat. Add the ground beef in an even layer and cook until browned, breaking it apart as it cooks. Drain the excess grease, leaving about one tablespoon in the pan.
Add the onion, garlic, bell pepper, sweet potatoes, chili powder, cumin, and oregano. Cook, stirring occasionally, until the vegetables start to soften, about 3 to 5 minutes.
Stir in the crushed tomatoes, black beans, and beef broth. Bring the mixture to a gentle simmer. Use this time to scrape any brown, burned bits off the bottom of the pan.
Transfer the skillet to the oven and bake uncovered for 35 to 40 minutes, or until the sweet potatoes are tender.
Sprinkle the shredded cheese evenly over the top and broil for 2 to 3 minutes, until melted and bubbling.
Season with salt and pepper to taste. Serve hot and enjoy.