Brown the ground beef with the onion and seasoning salt in a skillet & drain.
Add ground beef to the slow cooker then add in all of the remaining ingredients except the cream cheese.
Cook on high for 4 hours or low for 8 hours.
When there is about an hour left, add in the softened cream cheese. You may need to stir a couple times to ensure the cream cheese is thoroughly blended.
Serve with shredded cheddar, sour cream and tortilla chips.