Place ground beef, tomatoes, potatoes, carrot, bell pepper, onion, celery and garlic in your slow cooker and pour chicken stock over the top.
Season with chili powder, salt and pepper, then stir everything together. Cover slow cooker, turn on HIGH and cook for 3-4 hours, or until vegetables are softened.
Stir flour into heavy cream until no chunks remain, then pour mixture, along with cheddar cheese, into slow cooker.
Stir to combine, then cover and cook for another 20-30 minutes, then ladle into soup bowls, top with cheese and crumbled bacon, if using, and serve hot!