Cut open the chuck roast in a few locations, then place the roast in a slow cooker.
Sprinkle the garlic into the cuts in the roast, then pour the jar of pepperoncini (including the liquid) over the roast and add the Italian seasoning.
Cover the slow cooker, then cook on low for 6 to 8 hours.
Shred the roast, salt to taste, then stuff the rolls with the beef and pepperoncini peppers. Serve.