Add cream cheese, sour cream, dressing, chopped corned beef, sauerkraut in a small Crock Pot on high, stirring every 30 minutes.
Reduce heat to low after an hour and place two slices of Swiss Cheese on top.
Stir after 30 minutes. Ready after another 30 minutes for a total of 2 hours.
Note: Your crock pot may run a little warmer. After adding the cheese, let cook for 30 more minutes. If the cheese is melty after 30 minutes, the dip can be done. If not, cook for another 30 for a total of 2 hours.