Coat a slow cooker with cooking spray. Place the pork into the cooker. Pour the teriyaki sauce, vinegar, red pepper flakes, and garlic over the pork.
Cover and cook on low until the pork is tender (4-5hours). Remove the pork from the cooker, and whisk in the peanut butter until smooth. Chop the pork into large bite-sized pieces and then put it back into the cooker. Put the pepper in and stir to coat.
Cook for 60 minutes until the pork is very tender and the peppers are just tender.
Serve in bowls over rice with green onions, peanuts and limes for garnish.