01 - Heat a large skillet over medium heat. Add the ground beef and diced onion, cooking until the beef is browned and no longer pink. Drain off any excess fat.
02 - Transfer the beef mixture to the bottom of a slow cooker insert.
03 - Evenly layer the diced potatoes, kidney beans, corn, and diced tomatoes over the beef mixture.
04 - In a small mixing bowl, combine the condensed mushroom soup, beef broth, smoked paprika, garlic powder, dried oregano, black pepper, and salt. Stir until smooth and well incorporated.
05 - Pour the sauce mixture evenly over all ingredients in the slow cooker. Cover with the lid and cook on LOW setting for 6 hours, or until potatoes are fork-tender.
06 - During the final 15 minutes of cooking, sprinkle the shredded cheddar cheese over the top. Cover and allow the cheese to melt completely.
07 - Serve the casserole hot, garnished with fresh chopped parsley or sliced green onions if desired.