Pat the chuck roast completely dry with paper towels on all sides. Season generously with freshly ground black pepper.

Optional but recommended: Heat a large cast iron skillet over high heat with 1 tablespoon of avocado oil or neutral oil. Sear the roast for 3-4 minutes per side until a deep brown crust forms. This step adds flavor but can be skipped for a quicker prep.

Place the chuck roast in the bottom of a 6-quart slow cooker.

Sprinkle the entire au jus packet evenly over the top of the roast.

Sprinkle the entire ranch seasoning packet evenly over the au jus layer.

Arrange the whole pepperoncini peppers around and on top of the roast. Add 2 tablespoons of the pepperoncini brine from the jar.

Place the pats of unsalted butter directly on top of the seasoned roast. Do not add any additional liquid — the butter, pepperoncini brine, and beef's natural juices will create plenty of braising liquid.

Place the lid on the slow cooker and cook on LOW for 8 hours. Do not cook on HIGH — the low and slow method is essential for the collagen to break down properly and the beef to become truly fall-apart tender.

After 8 hours, the roast should be extremely tender and shred easily with two forks. Do not stir during cooking.

Using two large forks or tongs, shred the beef directly in the slow cooker, pulling it apart into large, generous chunks. Stir the shredded beef into the accumulated braising liquid.

Taste and adjust seasoning if needed. The braising liquid is your sauce — it should be rich, buttery, and deeply savory.

Serve immediately over mashed potatoes, cauliflower mash, egg noodles, or rice. Spoon plenty of the braising liquid over the top as gravy. Garnish with fresh parsley if desired.