Brown ground beef in large pot. Drain off grease. Add potatos, onions, peppers, celery, salt and bouillon cubes. Pour in water and bring to a boil. Reduce heat cover and simmer for 15 to 20 minutes or until vegetables are tender. Whisk flour into milk and slowly pour into pot with meat and vegetables. Stir until soup is thickened slightly. Mix in cheese and stir until melted.