Once cooked, gently stir from the bottom to coat the potatoes and meatballs in the thickened sauce. If the stew seems too thick, you can loosen it with a splash of additional warm beef broth; if it seems thin, leave the lid off and cook on HIGH for another 15 to 20 minutes to reduce slightly.
Taste and adjust seasoning if needed (the onion soup mix is salty, so you may not need extra salt). Ladle into bowls and serve hot.
Variations & Tips
For a creamier, richer stew, stir in 1/4 to 1/2 cup of sour cream or heavy cream at the very end of cooking, off the heat, to keep it from curdling. If you prefer a lighter flavor, swap the cream of mushroom soup for cream of chicken or cream of celery, keeping the rest of the recipe the same. You can also use turkey or chicken meatballs instead of beef for a slightly leaner dish; just be sure they are fully cooked, frozen meatballs. To add vegetables without complicating things, scatter 1 to 2 cups of frozen peas and carrots or green beans over the top of the meatballs during the last 30 to 45 minutes of cooking so they heat through but don’t overcook. For an herby twist, sprinkle in 1 teaspoon of dried Italian seasoning or a pinch of dried thyme with the soup mixture. If your family likes a bit of tang, finish the stew with a splash of Worcestershire sauce or a teaspoon of Dijon mustard to sharpen the savory flavors. Finally, if you need to feed a crowd, you can easily double the recipe in a larger slow cooker; just keep the potatoes in a relatively even layer on the bottom so they cook through, and extend the cooking time by about 30 to 60 minutes if the crock is very full.
