Best Ever Crockpot Meatball Sub Casserole (The Easiest Comfort Food Dinner!)
I first developed this Crockpot Meatball Sub Casserole on a particularly chaotic Tuesday night. The kids were hungry, I was exhausted, and the thought of assembling individual meatball subs made my brain hurt!
I needed a miracle dinner—something that delivered maximum flavor with minimum effort. That’s when the slow cooker swooped in to save the day!
This tested, family-favorite recipe takes all the delicious, cheesy flavor of a classic meatball sub and transforms it into the ultimate set-it-and-forget-it casserole. It truly is the perfect comfort food for any busy family looking for an easy dinner solution.
Why You’ll Love This Recipe
❤️ Effortless Comfort: This recipe uses pre-cooked meatballs and your slow cooker, meaning only 15 minutes of hands-on prep time.
- The Mess-Free Sub: It gives you all the flavor of a messy sub sandwich without needing to handle sticky rolls or leaky sauce at the table.
- Budget-Friendly: Using simple pantry staples and frozen meatballs keeps this meal affordable and accessible.
- Ultimate Crowd Pleaser: It doubles beautifully for potlucks or game days and is always a hit with kids and adults alike!
What You Need
You only need a few simple pantry staples for this recipe! We rely on frozen meatballs and jarred sauce to keep things fast, but feel free to swap in homemade versions if you have extra time.
Check the full printable recipe card below for detailed measurements and the complete list of ingredients.
Expert Tips for the Best Casserole
💡 Pro Tips for Success:
- Toasting the Bread: Lightly toasting or searing the bread cubes in a skillet with a little butter before adding them to the crockpot helps them hold their structure better and prevents them from getting too mushy in the sauce.
- The Cheese Layer: For the ultimate cheese pull, make sure to layer the mozzarella generously over the top and cook until the edges are bubbling and slightly browned.
- Meatball Quality: Using high-quality frozen meatballs makes a huge difference. Choose an Italian-style meatball for the best flavor foundation.
- Sauce Thickness: If your sauce looks too thin after adding the beef broth, leave the lid slightly ajar for the last hour of cooking to allow some liquid to evaporate.
Variations & Substitutions
One of the best things about casseroles is how easy they are to customize! Get creative with these substitutions:
- Keto/Low Carb: Omit the hoagie rolls entirely. Instead, serve the cheesy meatballs and sauce over zucchini noodles or spaghetti squash.
- Gluten-Free: Simply swap out the standard hoagie rolls for your favorite gluten-free dinner rolls or baguette cubes.
- Spice It Up: Add a pinch of crushed red pepper flakes to the sauce mixture for a lovely spicy kick.
- Cheese Swap: Try using provolone slices instead of mozzarella for a truly authentic meatball sub flavor.
Storage & Freezing
This casserole is fantastic for meal prepping and stores easily!
Storage: Allow the leftovers to cool completely. Transfer them to an airtight container and refrigerate for up to 3 days. Reheat gently in the microwave or oven until warmed through.
Freezing: I do not recommend freezing the finished casserole once the bread has been incorporated, as the texture of the bread will become very soggy upon thawing. However, you can easily freeze the cooked meatballs and sauce mixture (without the bread or cheese) for up to 3 months.
FAQ
Are frozen meatballs already cooked?
Yes, most store-bought frozen meatballs are fully cooked, which is why this recipe requires very little actual ‘cooking’ time—mostly just time to heat everything thoroughly and meld the flavors.
Can I make this with fresh, uncooked meatballs?
Absolutely, but you will need to adjust the cook time. Ensure the internal temperature of the meatballs reaches 165°F. You will likely need to cook them for 5-6 hours on LOW before adding the bread and cheese.
What is the best type of bread to use?
The best bread is anything sturdy! Hoagie rolls, stale French bread, or Italian bread cut into large cubes work best. Avoid very soft sandwich bread, as it dissolves too quickly.
I hope this Crockpot Meatball Sub Casserole becomes a new family favorite in your rotation. It truly saves the day!
Happy cooking, friends. Don’t forget to Pin this easy recipe for later!
Crockpot Meatball Sub Casserole (Best Easy Dinner)
Ingredients
- 24 frozen pre-cooked meatballs (about 2 lbs)
- 2 (24 oz) jars marinara sauce
- 1 teaspoon Italian seasoning
- 1/2 teaspoon garlic powder
- 1 cup beef broth or water
- 4 large hoagie rolls or 8 small dinner rolls, sliced or cubed
- 2 cups shredded mozzarella cheese
- 1/2 cup grated Parmesan cheese
- Fresh basil or parsley for garnish
Instructions
- Step 1 Combine meatballs, marinara sauce, Italian seasoning, garlic powder, and beef broth in a 6-quart crockpot. Stir well to combine.
- Step 2 Cook on LOW for 3-4 hours or HIGH for 2 hours, until the meatballs are heated through and the sauce is bubbling.
- Step 3 Slice the rolls into 1-inch cubes. If desired, lightly toast the bread cubes in a skillet for 2-3 minutes to prevent sogginess.
- Step 4 In the last 30 minutes of cooking, gently stir the hoagie roll cubes into the sauce mixture until they are coated.
- Step 5 Sprinkle the top generously with mozzarella and Parmesan cheese. Cover the crockpot and cook for 15-20 minutes, or until the cheese is completely melted and bubbly.
- Step 6 Garnish with fresh herbs (basil or parsley) and serve immediately.
Ingredients
- 24 frozen pre-cooked meatballs (about 2 lbs)
- 2 (24 oz) jars marinara sauce
- 1 teaspoon Italian seasoning
- 1/2 teaspoon garlic powder
- 1 cup beef broth or water
- 4 large hoagie rolls or 8 small dinner rolls, sliced or cubed
- 2 cups shredded mozzarella cheese
- 1/2 cup grated Parmesan cheese
- Fresh basil or parsley for garnish
