Heat a skillet over medium heat and brown the ground beef.
Add chopped onion and minced garlic and cook until softened.
Drain excess fat and transfer beef mixture to the slow cooker.
Add diced potatoes, corn, black beans, and cream of mushroom soup.
Season with chili powder, paprika, salt, and black pepper.
Stir all ingredients until well combined.
Cover and cook on low for 6 hours or until potatoes are tender.
Sprinkle shredded cheddar cheese over the casserole.
Cover and cook for an additional 10 minutes until cheese melts.
Garnish with fresh parsley and serve warm.