Prepare the Chuck Roast
Pat the chuck roast completely dry with paper towels. Remove any large pieces of excess fat from the surface. Place the roast directly in your slow cooker insert.
Create the Seasoning Blend
In a small bowl, combine paprika, garlic powder, onion powder, dried chives, dried dill, xanthan gum, salt, and black pepper. Whisk together thoroughly for about 30 seconds to ensure xanthan gum is evenly distributed.
Season the Roast
Generously rub the seasoning blend all over the chuck roast, coating every surface including the sides and bottom. Press the seasonings into the meat gently so they adhere.
Add Remaining Ingredients
Arrange the pepperoncini peppers around the roast in the slow cooker. Place the butter directly on top of the roast. Pour the beef broth and pepperoncini juice around (not over) the roast to keep the seasoning crust intact.
Slow Cook to Perfection
Cover and cook on low heat for 6-8 hours until the meat is fall-apart tender. The roast is done when a fork slides in easily and the meat shreds with minimal pressure. (Alternative: Cook on high for 4-5 hours if needed.)
Shred and Rest
Use two forks to shred the meat right in the slow cooker, breaking it into bite-sized pieces. Let the shredded meat rest in the gravy for 15-20 minutes before serving, stirring occasionally to absorb the flavors.
Serve
Spoon the meat with plenty of gravy onto plates. Serve over cauliflower mash, mashed turnips, cauliflower rice, or with roasted vegetables. Garnish with fresh parsley and extra pepperoncini if desired.