Meatball Sub Casserole gives you all the saucy, cheesy comfort of a meatball sandwich in a 9×13-inch baking dish. Italian bread makes the base, a seasoned cream cheese layer goes in the middle, and homemade beef meatballs bake under marinara and mozzarella.
I like this version when I want the flavor of meatball subs without building a pile of individual sandwiches. It is rich, filling, and easy to portion straight from the pan.
The texture is softer than a toasted sub, and that is intentional. The bread absorbs some sauce as the casserole bakes, while the cream cheese mixture keeps the middle creamy instead of turning into plain soggy bread.
For more comfort-food dinners, browse our Casserole recipes and Beef recipes.
What Makes This Casserole Different
The meatballs are cooked before the casserole is assembled. That means the second bake is really about bringing the layers together: warming the sauce, softening the bread, and melting the cheese.
I also like that the cream cheese layer sits between the bread and sauce. It gives the casserole some structure and adds a tangy, savory layer that balances the tomato sauce.
Ingredient Notes
Ground beef: A moderately lean beef works well. You want enough fat for flavor without leaving the baking sheet greasy.
Italian bread: Cut it about 1 inch thick and fit the slices snugly across the bottom of the pan. Depending on the loaf, you may not need every slice.
Cream cheese: Let it soften first. Cold cream cheese is difficult to spread over bread without tearing it.
Mozzarella: The cheese is divided between the middle and top. Freshly shredded mozzarella melts especially well, but bagged shredded cheese is fine too.
Marinara: Use a sauce you already enjoy on pasta because its flavor comes through clearly in the finished casserole.
Ingredients
For the Meatballs
- 1/3 cup chopped green onion
- 1/4 cup seasoned breadcrumbs
- 3 tablespoons grated Parmesan cheese
- 1 pound ground beef
For the Casserole
- 1 loaf Italian bread, cut into 1-inch slices
- 8 ounces cream cheese, softened
- 1/2 cup mayonnaise
- 1 teaspoon Italian seasoning
- 1/4 teaspoon black pepper
- 2 cups shredded mozzarella cheese, divided
- 1 (28-ounce) jar spaghetti or marinara sauce
- 1 cup water
- 2 garlic cloves, minced
How to Make Meatball Sub Casserole
- Preheat the oven to 400°F.
- In a large bowl, combine the green onion, seasoned breadcrumbs, and Parmesan.
- Add the ground beef and mix gently until everything is evenly distributed.
- Shape the mixture into meatballs about 1 inch in diameter.
- Arrange the meatballs on a baking sheet and bake for 15 to 20 minutes, or until the centers reach 160°F.
- Remove the meatballs from the oven and reduce the oven temperature to 350°F.
- Arrange the Italian bread slices in a single layer across the bottom of an ungreased 9×13-inch baking dish. Trim pieces as needed to cover the base.
- Stir together the softened cream cheese, mayonnaise, Italian seasoning, and black pepper until smooth.
- Spread the cream cheese mixture over the bread and sprinkle with 1/2 cup mozzarella.
- In another bowl, stir together the marinara, water, and minced garlic.
- Add the cooked meatballs to the sauce and gently coat them.
- Spoon the meatballs and sauce evenly over the bread layer.
- Sprinkle the remaining 1 1/2 cups mozzarella over the top.
- Bake uncovered for about 30 minutes, or until the sauce is bubbling and the cheese is fully melted.
- Let the casserole rest for 5 to 10 minutes before serving.
How to Keep the Bread from Getting Too Wet
Some softness is part of this recipe, but I would not assemble the whole casserole hours before baking. Once the sauce sits on the bread for a long time, the base can become much softer than intended.
If you want to get ahead, make the meatballs, stir together the sauce, and mix the cream cheese layer earlier in the day. Then assemble everything shortly before it goes into the oven.
Easy Ways to Change It Up
Fully cooked frozen meatballs are the easiest shortcut. Heat them according to the package directions before adding them to the sauce.
For a more classic sub flavor, replace part of the mozzarella with provolone. A pinch of crushed red pepper in the marinara also works if you want a little heat.
What to Serve with It
This casserole is already rich, so I would keep the sides simple: a green salad, roasted broccoli, green beans, or another crisp vegetable works well.
Storage and Reheating
Refrigerate leftovers in a covered container for up to 3 to 4 days. The bread will soften more as it sits, but the casserole still reheats well.
Warm individual portions in the microwave, or cover a larger portion and reheat it in the oven until hot throughout.
Frequently Asked Questions
Can I use frozen meatballs?
Yes. Use fully cooked meatballs and heat them according to the package directions before adding them to the sauce.
Can I assemble the casserole ahead?
I would prep the separate components ahead rather than assembling the whole dish. Put it together shortly before baking for the best bread texture.
Can I use provolone?
Absolutely. Provolone works especially well with the meatball-sub flavor and can replace part or all of the mozzarella.
