These Slow Cooker Meatballs with Onions and Gravy are tender, juicy, and simmered in a rich homemade brown gravy with soft, caramelized onions. Serve them with creamy mashed potatoes for an easy, comforting family dinner that practically cooks itself.
Prep Time: 25 minutes
Cook Time: 4–6 hours
Total Time: About 4 hours 25 minutes
Servings: 6
Yield: About 20–24 meatballs
Why You’ll Love This Recipe
- Tender homemade beef meatballs
- Rich, savory onion gravy
- Easy slow cooker preparation
- Simple everyday ingredients
- Perfect with mashed potatoes
- Excellent make-ahead family dinner
- Cozy comfort food for fall and winter
Ingredient Notes
Ground beef: An 85/15 ground beef works particularly well. It has enough fat to keep the meatballs tender without making the gravy excessively greasy.
Breadcrumbs: Plain breadcrumbs help bind the meatballs while keeping them tender.
Milk: Moistens the breadcrumbs and prevents dense, dry meatballs.
Onions: Yellow onions become soft and sweet during slow cooking and add lots of flavor to the gravy.
Beef broth: Use a good-quality low-sodium beef broth so you can control the salt.
Worcestershire sauce: Adds depth and savory flavor to the gravy without overpowering it.
Cornstarch: Added near the end to thicken the gravy to the perfect consistency.
Ingredients
For the Meatballs
- 2 lb (900 g) ground beef
- ¾ cup (75 g) plain breadcrumbs
- ⅓ cup (80 ml) milk
- 1 large egg
- 2 garlic cloves, finely minced
- 1 tablespoon Worcestershire sauce
- 1 teaspoon onion powder
- 1 teaspoon garlic powder
- 1 teaspoon kosher salt
- ¾ teaspoon freshly ground black pepper
- ½ teaspoon dried thyme
- 2 tablespoons finely chopped fresh parsley
- 1 tablespoon olive oil, for browning
For the Onion Gravy
- 2 large yellow onions, thinly sliced
- 2 tablespoons unsalted butter
- 2½ cups (600 ml) low-sodium beef broth
- 1 tablespoon Worcestershire sauce
- 1 teaspoon Dijon mustard
- ½ teaspoon dried thyme
- ½ teaspoon garlic powder
- ½ teaspoon freshly ground black pepper
- Salt, to taste
To Thicken the Gravy
- 3 tablespoons cornstarch
- 3 tablespoons cold water
For Serving
- Creamy mashed potatoes
- Fresh parsley
- Freshly ground black pepper
Instructions
1. Prepare the Meatball Mixture
Place the breadcrumbs and milk in a large bowl. Stir and let them sit for about 5 minutes.
Add the ground beef, egg, garlic, Worcestershire sauce, onion powder, garlic powder, salt, pepper, thyme, and parsley.
Using clean hands or a fork, gently combine the ingredients until just incorporated.
Do not overmix. Overworking ground beef can make meatballs firm and dense.
2. Shape the Meatballs
Shape the mixture into approximately 20–24 meatballs, about 1½ inches each.
They don’t need to be perfectly round. Slightly irregular meatballs have a more homemade appearance and texture.
3. Brown the Meatballs
Heat the olive oil in a large skillet over medium-high heat.
Working in batches if necessary, brown the meatballs for approximately 1–2 minutes per side.
You are not trying to cook them completely. The goal is simply to develop a flavorful browned exterior.
Transfer the browned meatballs to a plate.
4. Cook the Onions
Reduce the heat to medium.
Add the butter and sliced onions to the same skillet.
Cook for 7–10 minutes, stirring occasionally, until the onions soften and begin to turn golden.
Scrape up the browned bits from the bottom of the skillet as the onions cook. They add excellent flavor to the gravy.
5. Prepare the Gravy
Pour about ½ cup of the beef broth into the skillet and stir, scraping the bottom to loosen any remaining browned bits.
Add the Worcestershire sauce, Dijon mustard, thyme, garlic powder, and black pepper.
Stir well.
6. Assemble the Slow Cooker
Transfer the onions and skillet liquid to the bottom of the slow cooker.
Arrange the browned meatballs over the onions.
Pour in the remaining beef broth.
The meatballs don’t need to be completely submerged.
Cover with the lid.
7. Slow Cook
Cook on:
LOW for 5–6 hours, or
HIGH for 3–4 hours
The meatballs are ready when they are tender and have reached an internal temperature of 160°F (71°C) for ground beef.
For the most tender result, I recommend the LOW setting.
8. Thicken the Onion Gravy
About 20–30 minutes before serving, combine the cornstarch and cold water in a small bowl until completely smooth.
Gently stir the slurry into the liquid around the meatballs.
Cover and continue cooking on HIGH for approximately 15–25 minutes, or until the gravy has thickened.
If necessary, add a little more cornstarch slurry for a thicker gravy.
Taste and adjust the salt and pepper.
9. Serve
Place the meatballs, caramelized onions, and gravy in a serving dish.
Spoon extra onion gravy over individual portions as desired and finish with a little fresh parsley and cracked black pepper.
Tips for the Best Meatballs
Don’t overwork the beef. Mix only until the ingredients are combined.
Brown the meatballs first. This extra step gives them much better color and flavor and helps them hold their shape in the slow cooker.
Slice the onions rather than chopping them. Long, soft pieces of onion are part of what makes this gravy so good.
Use low-sodium broth. Worcestershire sauce already contains salt, so this makes seasoning easier to control.
Thicken at the end. Adding cornstarch at the beginning can produce an inconsistent gravy.
Cook on LOW when possible. The longer, gentler cooking time produces particularly tender meatballs.
Easy Creamy Mashed Potatoes
For a side similar to the photo, you’ll need:
- 2 lb (900 g) Yukon Gold or Russet potatoes
- 4 tablespoons unsalted butter
- ½–¾ cup (120–180 ml) warm milk
- Salt and black pepper, to taste
Peel and cut the potatoes into chunks. Place them in a large pot, cover with cold salted water, and bring to a boil.
Cook for 15–20 minutes, or until fork-tender.
Drain thoroughly and return the potatoes to the warm pot for 1–2 minutes to allow excess moisture to evaporate.
Mash with the butter, then gradually add warm milk until creamy. Season with salt and pepper.
Keep the mashed potatoes in a separate serving bowl and spoon the meatballs and gravy alongside them when serving.
Variations
Mushroom Meatballs and Gravy
Add 8 oz (225 g) sliced mushrooms to the skillet with the onions.
Extra Onion Version
Use three large yellow onions for an even richer onion gravy.
Creamy Gravy
At the end of cooking, stir ¼ cup heavy cream into the finished gravy.
Turkey Meatballs
Ground turkey can replace the beef. Cook ground turkey meatballs to an internal temperature of 165°F (74°C).
Make Ahead
The meatballs can be shaped and refrigerated in an airtight container for up to 24 hours before cooking.
You can also brown them in advance and refrigerate them until you’re ready to assemble the slow cooker.
Storage
Allow leftovers to cool before transferring them to an airtight container.
Store the meatballs and gravy in the refrigerator for 3–4 days.
For best results, keep the mashed potatoes in a separate container.
Freezing
The cooked meatballs and onion gravy freeze very well.
Transfer completely cooled meatballs and gravy to a freezer-safe container and freeze for up to 3 months.
Thaw overnight in the refrigerator before reheating.
I recommend making fresh mashed potatoes rather than freezing them with the meatballs.
Reheating
Reheat the meatballs and gravy gently in a covered saucepan over medium-low heat.
If the gravy has become too thick, add a splash of beef broth or water.
You can also microwave individual portions until thoroughly heated.
FAQ
Do I have to brown the meatballs first?
Technically, you can place raw meatballs directly into the slow cooker, but browning is strongly recommended. It adds flavor, improves their appearance, and helps them hold together.
Can I use frozen meatballs?
Yes. Fully cooked frozen meatballs can be used for a quicker version. Add them directly to the slow cooker with the onions and gravy ingredients and cook until thoroughly heated. The texture and flavor will differ somewhat from homemade meatballs.
Why is my gravy too thin?
Slow cookers retain moisture, so sauces sometimes remain thinner than expected. Add the cornstarch slurry near the end and allow the gravy to cook on HIGH until thickened.
What if the gravy becomes too thick?
Simply stir in a small amount of warm beef broth until it reaches your preferred consistency.
What goes well with meatballs and gravy?
Mashed potatoes are my first choice, but these meatballs are also delicious with buttered egg noodles, rice, roasted potatoes, or steamed vegetables.
Can I prepare this recipe overnight?
For food safety, don’t leave the assembled ingredients sitting in an unplugged slow cooker overnight. Prepare the components ahead, refrigerate them, and assemble and cook when ready.
Conclusion
These Slow Cooker Meatballs with Onions and Gravy are everything a comfort-food dinner should be: tender beef meatballs, soft onions, and plenty of rich savory gravy.
Serve the meatballs and gravy in one dish with a bowl of creamy mashed potatoes alongside for an easy family meal that’s especially satisfying on a cold evening.
Lea recipes 
Leave a comment