Add meatballs to the slow cooker.
Frozen meatballs go in straight—no thawing required. Homemade? Even better.
Layer in mushrooms and aromatics.
Scatter sliced mushrooms, onion, and garlic over the meatballs. No need to stir yet.
Mix the gravy base.
In a bowl, whisk together cream of mushroom soup, beef broth, Worcestershire sauce, salt, and pepper. Pour it over everything like you know what you’re doing.
Cook low and slow.
Cover and cook on LOW for 4–5 hours or HIGH for 2–3 hours. The meatballs should be tender and fully coated in gravy.
Finish with cream.
Stir in heavy cream or milk during the last 20–30 minutes. This is where things get luxuriously creamy.
Taste and adjust.
Add more salt or pepper if needed. Trust your taste buds—they’re smarter than recipes sometimes.
Serve it up.
Spoon generously over mashed potatoes, rice, egg noodles, or biscuits. Sprinkle with parsley if you’re feeling fancy.