To a slow cooker, add the pork roast, onion if using, and pepperoncini juice. Sprinkle roast with dressing mix, gravy mix, and peppers. Top with butter cubes.
Cook 8-10 hours on low or 4-5 hours on high, or until pork is fork tender.
Remove the roast and peppers from the slow cooker. Skim some fat from the juices if desired.
For optional gravy, mix cornstarch and water to create a slurry. Stir slurry into the juices in the slow cooker, cover, and turn to high. Cook for 5-10 minutes, or until slightly thickened.
Shred pork using shredding tongs or two forks. Mix pork in with the juices or gravy. Serve with mashed potatoes, egg noodles, or rice.
Notes
If you check the roast and it’s not fork tender, cook for another 30 minutes and check again.
*If the pork roast has a large fat cap, reduce the amount of butter. Butter can be omitted, but adds great flavor.