Add broth, then pour ranch seasoning and and dry onion soup over the meat but don't mix.Rest the butter stick on top of meat, and place Peperoncini around the meat.
Lock lid in place, turn steam valve to sealing.Press pressure cook mode and adjust time to 90 minutes.When done, let pot run on natural release for 15 minute.
Release any remaining pressure by turning pressure valve to venting, unlock lid and carefully remove Peperoncini to a small bowl and set aside (you may leave them in if you want the dish to be spicy, otherwise try to remove them without breaking them, the seeds hold the heat!).
Using two forks, shred the meat (it will come apart very easily)Return meat to pot and stir into the gravy mixture.Lock lid back on and let rest until ready to serve (it will stay warm for a long time in the pot). Serve with a side of mashed potatoes, rice, egg noodles or on a bun!