Brown the ground beef and onion together, do this directly in the slow cooker if you have a Multi-Cooker, or brown the meat in a skillet on the stove. Drain the fat from the meat, add the meat to the slow cooker (if you browned it on the stove).
Sprinkle the meat with the salt and pepper.
Add half of the cheese, sour cream, pinto beans, and rice to the meat. Stir, then flatten out. Sprinkle with remaining cheese.
Cover and cook on HIGH for 2 hours, without opening the lid during the cooking time.
When the cooking time is through, sprinkle on the olives and tomatoes. Serve with tortilla chips and enjoy!