Place the beef chuck roast into the bottom of a large slow cooker, fat side up. There’s no need to brown it first—my uncle always said the slow cooker and the beer would do all the work.
Sprinkle the dry onion soup mix evenly over the top and sides of the roast, pressing it in lightly so it sticks to the surface.
Slowly pour the dark beer around the roast in the slow cooker, avoiding rinsing all the soup mix off the top. The liquid should come at least one-third of the way up the sides of the meat.
Cover the slow cooker with the lid and cook on LOW for 8 to 10 hours, or until the beef is very tender and easily pulls apart with a fork. For a smaller roast (around 3 lb), start checking at 8 hours.
Once the roast is done, carefully transfer it to a large plate or platter. Use two forks to gently pull it into large chunks, keeping some bigger pieces so it looks hearty and rustic.
Stir the cooking liquid in the slow cooker to combine; it should be a rich, dark, glossy gravy. If there’s excess fat on top, you can skim it with a spoon. Spoon the hot gravy over the pulled beef on the plate so it’s glistening and falling apart in the sauce.
Serve the beef roast right away while it’s steaming hot, making sure everyone gets plenty of the dark, savory gravy over their portion.
Variations & Tips
For a slightly thicker gravy without adding more ingredients, remove the lid for the last 30 to 45 minutes of cooking and let some of the liquid reduce, or gently simmer the strained cooking liquid on the stovetop while the roast rests.
If you prefer less richness, use half the packet of onion soup mix and add a splash of water to mellow it out. You can also swap the beef chuck roast for a similar marbled cut like beef arm roast or bottom round, but chuck will give you the most fall-apart texture.
For make-ahead prep, assemble everything in the slow cooker insert the night before, cover, and refrigerate; in the morning, pop it into the base and start cooking before work. Leftovers are fantastic piled onto toasted rolls as hot beef sandwiches or tucked into tortillas for quick tacos, with the dark beer gravy drizzled over the top.
