In a very large skillet over medium-heat, cook the ground beef, bell pepper, onion and garlic until the meat is browned and the vegetables are tender; drain the fat and discard. Stir the tomatoes and juices and the tomato paste into the beef mixture. Bring to boiling; reduce heat. Simmer, uncovered, for 5 minutes.
Spoon the beef mixture into the bottom of an ungreased 2-quart rectangular baking dish. In a medium bowl, stir together the soup and sour cream; spread over the meat mixture in the baking dish. Sprinkle the potatoes over the top of the soup mixture. Sprinkle with the seasoned salt.
Bake, uncovered, for 40 to 45 minutes or until heated through and the potatoes are light brown. If desired, serve with assorted toppers.