Oven Method:

1. Preheat oven to 275°F and position rack in the middle.
2. Heat olive oil in a Dutch oven over medium-high heat. Sear roast on all sides until browned. If using a roasting dish, sear meat in a skillet first.
3. Remove from heat, let cool slightly, then pour pepperoncini juice over the roast.
4. Place pepperoncini around the roast, sprinkle with au jus and ranch seasoning, and add butter on top.
5. Cover and roast for 3-4 hours (about 3.5 hours for a 3 lb roast) until fork-tender.
6. Shred with two forks and mix with the juices before serving.

Slow Cooker Method:

1. Heat olive oil in a skillet over medium-high heat and sear roast on all sides.
2. Transfer roast to slow cooker. Pour pepperoncini juice over it, add pepperoncini, au jus mix, ranch seasoning, and butter.
3. Cover and cook on LOW for 8 hours until the beef is fall-apart tender.
4. Shred with two forks and mix with the juices before serving.

Instant Pot Method:

1. Cut the roast into 3-4 pieces.
2. Heat olive oil in Instant Pot on Sauté mode and sear meat in batches.
3. Turn off Sauté, then add all meat, ¾ cup water, and pepperoncini juice.
4. Place pepperoncini, au jus mix, ranch seasoning, and butter on top.
5. Seal the lid and set Instant Pot to High Pressure for 60 minutes.
6. Let the pressure release naturally for 15 minutes, then quick release.
7. Shred with two forks and mix with the juices before serving.