Add all sauce ingredients in slow cooker pot and mix together.
Add pork roast and place whole cream cheese brick on top. Secure lid and cook for 5½ hours on low.
Remove lid and turn off slow cooker. Using two forks, pull the pork while mixing in the cream cheese.
Remove a ¼ cup of sauce and stir in with cornstarch. Return slurry to slow cooker, increase heat to high and secure lid. Let cook for remaining 30 minutes.
Put a portion of pork on the bottom bun (with a bit of the sauce). The put on top bun and press down slightly to hold it all together.