This slow cooker 4-ingredient onion soup pot roast is the kind of no-fuss comfort food that feels like it came straight from Grandma’s kitchen. It leans on a classic Midwestern shortcut: dry onion soup mix. With just a chuck roast, onion soup mix, onions, and beef broth, you get a deeply savory, glossy gravy and beef so tender it practically collapses under a fork. This is the sort of recipe you make on a busy weekday morning and come home to in the evening, wondering how four ingredients could transform into something this rich and satisfying.
Serve this pot roast straight from the slow cooker, spooning the onions and glossy brown gravy over each portion of beef. It’s wonderful over creamy mashed potatoes, buttered egg noodles, or a bed of rice to catch all the juices. Add a simple green side—steamed green beans, roasted carrots, or a crisp salad with a tangy vinaigrette—to balance the richness. A slice of crusty bread is perfect for mopping up the extra gravy, and if you enjoy wine, a medium-bodied red like a Merlot or Cabernet Franc pairs nicely with the savory onion flavors.
Slow Cooker 4-Ingredient Onion Soup Pot Roast
Servings: 6

Ingredients
3 to 3 1/2 pounds beef chuck roast
2 (1-ounce) packets dry onion soup mix
2 large yellow onions, thinly sliced
2 cups beef broth (low-sodium preferred)
Directions
Prepare the onions by peeling and thinly slicing them into half-moons. Scatter the sliced onions evenly over the bottom of a 6-quart slow cooker to create a bed for the roast. This not only flavors the beef but also helps build that rich, onion-forward gravy.
Pat the chuck roast dry with paper towels. This helps it brown slightly as it cooks and keeps the surface from steaming. Place the roast directly on top of the sliced onions in the slow cooker.
Sprinkle the dry onion soup mix evenly over the top and sides of the roast. Use your hands to gently pat the mix onto the surface so it adheres and seasons the meat thoroughly. The soup mix will dissolve into the cooking liquid and create a deep, savory base.
Pour the beef broth around the sides of the roast, being careful not to wash all of the onion soup mix off the top. You want some of that seasoning to stay on the meat while the rest mingles with the broth and onions to form the glossy, dark brown gravy.
Cover the slow cooker with the lid and cook on LOW for 8 to 10 hours, or until the roast is very tender and easily pulls apart with a fork. Low and slow is key here; this long, gentle cooking time is what makes the beef as tender as Grandma remembers.
Once the roast is done, use two forks to gently pull it into large chunks right in the slow cooker, leaving some pieces intact for that classic pot roast look. Stir the onions and cooking juices around the meat so everything is coated in the rich gravy.
Taste the gravy and adjust the seasoning only if needed; the onion soup mix is quite salty, so you may find no extra salt is necessary. If you’d like a slightly thicker gravy, you can briefly remove a cup of the hot liquid, whisk in 1 to 2 teaspoons of cornstarch until smooth, then stir it back into the slow cooker and let it bubble on HIGH for 10 to 15 minutes.
Serve the pot roast hot, spooning plenty of the translucent caramelized onions and dark, glossy gravy over each portion of beef. Keep any leftovers in an airtight container in the refrigerator for up to 3 days; the flavors deepen even more by the next day.

Variations & Tips
Because this recipe is intentionally just four ingredients, keep any add-ins optional and understand they will change that strict count. For extra richness, you can sear the chuck roast in a hot skillet with a bit of oil before placing it in the slow cooker; browning develops more flavor, but it’s not required. If you prefer a thicker, stew-like consistency, whisk 1 to 2 tablespoons of cornstarch with cold water and stir it into the hot cooking liquid at the end, then cook on HIGH until slightly thickened. For a deeper onion profile, swap one of the yellow onions for a sweet onion, which will melt into the gravy. If you like a bit of tang to balance the richness, stir in 1 to 2 teaspoons of Worcestershire sauce or a splash of red wine vinegar at the end of cooking. Leftovers make excellent open-faced sandwiches: reheat the beef and onions, pile them onto toasted bread, and spoon the gravy over the top. You can also shred the beef more finely and use it as a filling for baked potatoes or as a topping for buttered noodles. If sodium is a concern, choose a reduced-sodium onion soup mix and low-sodium beef broth, then season to taste at the end.