Since there are so many different types of crock pots/slow cookers and some of the newer ones cook faster then the older models; check to see if the cheese has melted after about 1 hour.
If you have an older crock pot you may need to cook this as long as 4 hours.
Brown the ground beef in a skillet. Drain the fat and transfer a crock pot. Add all of the remaining ingredients. Cover and cook on LOW 1-4 hours or until cheese is melted. (Refer to personal note for further information).
Switch to a warm setting and/or leave on LOW and serve with tortilla chips.