Heat a large, nonstick skillet over medium-high heat. Spray with nonstick spray. Add the roast halves, browning on all sides. Place the roast halves in the insert of a slow cooker that has been sprayed with nonstick spray.
In a medium bowl, mix the cranberry sauce, brown sugar and mustard; pour over the roast in the crockpot. Cover with the lid and cook on HIGH for 1 hour. Reduce to LOW and cook for 6 hours. Remove the roast from the crockpot, reserving the cranberry mixture in the crockpot. Set the roast aside, keeping it warm.
In a large, microwave-safe bowl, whisk together the cornstarch and water until well mixed. Scoop the cranberry mixture into the large bowl and then whisk the cornstarch and cranberry mixture together. Place the bowl in the microwave and cook on HIGH for 2 minutes, or until thickened.
Place the pork roast on a platter and use two forks to shred it apart. Top with the cranberry sauce and serve immediately.
Notes
Serve with couscous - it's great with a little drizzle of the sauce.
If you're preparing this meal as GLUTEN FREE, just make sure that the brands of cranberry sauce and mustard that are noted as being gluten free.