This leftover spaghetti casserole recipe is an easy dinner meal made with leftover spaghetti noodles tossed in pasta sauce, then topped with cheese and baked until golden brown.
What to do With Leftover Spaghetti?
When I make spaghetti, there’s usually always leftover noodles. I’m not big on spaghetti for leftovers for lunch, so instead I prefer making a casserole with my leftover spaghetti for the following night! In fact this casserole is now such a hit in my house, I almost always make extra spaghetti with the thought that I’ll be making this casserole in the next couple nights!
Next time you have leftover spaghetti, don’t you dare toss it, make this Leftover Spaghetti Casserole!
Here’s a recipe video I made to show you how easy it is to make!
How long is leftover spaghetti good for?
When properly stored in a refrigerator, cooked spaghetti is good for up to 4 days. When you make spaghetti make sure to get your cooked leftover noodles in the refrigerator within 2 hours.
How To Make Spaghetti Casserole
If you have leftover pasta and sauce, you’re pretty much all set, but even if you don’t, it’s easy to cook up some noodles for this casserole.
Start by mixing leftover spaghetti noodles and pasta sauce with an egg, Italian seasoning, Parmesan cheese and ground beef or shredded chicken (note: meat is optional).
Place the spaghetti mixture into a baking dish and bake uncovered for 30 minutes.
After 30 minutes, remove from the oven and sprinkle mozzarella cheese and mushrooms on top and bake for an additional 10 minutes. And for those folks who don’t like mushrooms, skip them! We’re mushroom lovers in our house, so we always add them in!
Bake until cheese is melted and golden brown.
I hope you enjoy this Leftover Spaghetti Casserole!
- If you have the time, grate your own mozzarella cheese. Pre-shredded cheeses often have anti-caking agents that prevent the cheese from melting well.
- Use any favorite marinara sauce for this recipe. You can also make your own homemade tomato sauce, my favorite is Cherry Tomato Sauce. You could even use an alfredo sauce if preferred.
- If you’re a meat eater, add cooked ground beef, Italian sausage or shredded chicken to this dish.
Put Your Spin on This Casserole
We loved this recipe as-is, but there are so many small changes to the ingredients you can make to customize it to your preferences.
- Meat: Add cooked chicken or if you have leftover ground beef, mix that in with the noodles. Ground turkey, turkey sausage or Italian sausage would also work great.
- Noodles: Spaghetti noodles are just one of the many different types of pasta that will work in this dish. Feel free to use penne, bow tie or rigatoni noodles, depending on what you have on-hand or leftover.
- Vegetables: Add sautéed vegetables to the sauce and noodle mixture, such as spinach, zucchini or bell peppers. And if you don’t love mushrooms, leave them off the top.
- Cheese: Instead of mozzarella try another cheese that melts well like provolone or cheddar.
- Topping: You can add a crispy topping to the dish by mixing breadcrumbs with melted butter and grated Parmesan cheese. Just pour the mixture over the top of the pasta after adding the mozzarella and before baking it for the second time.
Can I make this ahead of time?
Spaghetti Casserole can be made up to 24 hours ahead of time. Simply cover and refrigerate the baking dish until you’re ready to bake the meal. Note: Leftover spaghetti is only good for up to 4 days.
Other Leftover Recipes:
Leftover Rice Tacos
Mashed Potato Patties (uses leftover mashed potatoes)
50 Ways To Use Leftover Egg Yolks
50 Best Buttermilk Recipes
How To Freeze Cake
How to Freeze Leftover Half & Half Milk
Easy Way to Freeze Mashed Potatoes
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Leftover Spaghetti CasserolePrint
- 8 ounces leftover spaghetti noodles
- 1 cup pasta sauce
- 1 egg beaten
- 1 teaspoon Italian seasoning
- 1/4 cup Parmesan cheese
- 1 cup cooked ground beef or shredded chicken OPTIONAL
- 1/2 cup mozzarella cheese
- 1/2 cup mushrooms chopped
- Preheat oven to 350 degrees F.
- In a large bowl add spaghetti noodles, pasta sauce, egg, Italian seasoning and Parmesan cheese. Optional: Add in cooked ground beef or chicken if you are using it. Mix to fully combine all the ingredients.
- Pour the spaghetti mixture into a 9×9 baking dish and bake uncovered for 30 minutes.
- Remove from the oven and sprinkle mozzarella cheese and mushrooms on top and bake for an additional 10 minutes until cheese is melted.