Heat olive oil in a large skillet over medium heat.
Add ground beef and cook until browned, draining excess fat if necessary.
Add diced onion and cook for 2 to 3 minutes until softened.
Stir in minced garlic and cook for 30 seconds until fragrant.
Add sweet potatoes, diced tomatoes, kidney beans (if using), and beef broth to the skillet.
Season with chili powder, paprika, cumin, salt, and black pepper and stir to combine.
Cover and simmer for 15 to 20 minutes, stirring occasionally, until sweet potatoes are tender.
Sprinkle shredded cheddar cheese over the skillet and cover again for 2 to 3 minutes until the cheese melts.
Garnish with sour cream, green onions, and cilantro as desired and serve warm.