Step 3: Mix the Sauce
In a bowl, whisk together the cream of mushroom soup, onion soup mix, and beef broth. Pour the mixture over the roast, making sure some of it seeps down into the onions.
Step 4: Cook
Cover and cook on LOW for 8–10 hours or on HIGH for 4–5 hours, until the meat is very tender and easy to shred.
Step 5: Finish and Serve
Remove the roast and slice it against the grain. Stir the gravy in the slow cooker, then return the sliced meat to the sauce. Let it sit on the warm setting for 10–15 minutes before serving.
Tip: Letting the meat rest in the gravy helps it absorb more flavor, making each bite extra juicy and delicious.