Season chuck roast generously with salt and pepper. Rub flour evenly over the surface of the meat.
In a large saute pan, warm oil over high heat until very hot but not smoking. Sear the roast until browned and crusty on all sides, about 15 minutes total.
Place roast in the pot of a slow cooker. Pour beef broth around the roast. Sprinkle Ranch seasoning over the roast, place butter on top and scatter pepperoncini over and around the roast. Cover the slow cooker and set on low heat for 7-8 hours.
When ready, shred the meat and mix with the sauce in the slow cooker. Serve over bread, egg noodles or potatoes.