Place the chuck roast fat-side up in a 4-6 quart slow cooker and sprinkle both seasoning packets evenly over the top.
3 pound chuck roast, 1 packet ranch seasoning mix, 1 packet au jus gravy mix
Cut the butter into 4 pieces and place them on top of the seasoned roast, then arrange 6-8 whole pepperoncini peppers around the meat.
4 tablespoon butter, 7 whole pepperoncini peppers
Pour beef broth around the edges of the roast without washing off the seasonings, then cover and cook on low for 7-8 hours until the beef reaches 195°F internal temperature.
0.75 cup beef broth
Remove the roast from the slow cooker and let it rest for 10 minutes on a cutting board to redistribute the juices.
Shred the meat with two forks or tongs and return it to the pot, stirring to coat with the sauce before serving.
3 pound chuck roast