Indulge in all the comforting flavors of lasagna without the guilt with this creamy Spaghetti Squash Lasagna Casserole. A perfect blend of hearty tomato sauce, creamy ricotta cheese, and tender strands of spaghetti squash, this vegetarian dish is a low-carb twist on a classic favorite.
This cheesy vegetarian spaghetti squash casserole is the epitome of comfort food meets healthy eating. It's one of my favorite spaghetti squash recipes and is a great recipe to try if you've never cooked this winter squash before.
With its creamy texture, savory tomato sauce, and gooey cheese topping, this spaghetti squash lasagna satisfies all your cravings while keeping your carb count low.
You can also try my cheesy Italian spaghetti squash boats, which are topped with a hearty meat sauce and plenty of mozzarella cheese.
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A Nutritious Lasagna
Lasagna is the ultimate comfort food. This creamy vegetarian spaghetti squash lasagna casserole is a nutritious spin on traditional lasagna. It has all the great flavors of traditional lasagna that we love but in a lighter and more nutritious package!
This comforting and light dish swaps out pasta for tender strands of spaghetti squash. But don't worry- this cheesy casserole will still satisfy your cravings thanks to the rich flavors and plenty of ooey, gooey cheese!
Spaghetti squash is a culinary rock star- low in calories, packed with nutrients, and incredibly versatile. Its spaghetti-like strands have a mild flavor and can be used in a wide variety of recipes, from main dishes to hearty side dishes.
The strands of squash are tossed with creamy ricotta cheese and chopped spinach. It’s then layered with tomato sauce, mozzarella, and parmesan cheese and baked in the oven until it’s bubbling with cheesy goodness. Packed with protein and fiber, this dish will keep you feeling full and satisfied.
Doctor's Tips
- Spaghetti squash is packed with nutrients like beta carotene, vitamin C, and dietary fiber. It's a delicious low-calorie substitute for pasta for anyone watching their carb intake or trying to eat more vegetables.
- Spaghetti squash is a nutritious and low-carb alternative to pasta dishes or rice. You can pair it with traditional tomato sauce and meatballs or serve it alongside creamy chicken or fish dishes to soak up the sauce.
Why You'll Love This Dish
- Lightened up comfort food- This cheesy casserole is a healthier twist on traditional lasagna, offering all the comforting flavors without the guilt.
- Nutritious- Spaghetti squash is rich in nutrients including beta carotene, vitamin C and fiber.
- Low carb- This low-carb dish is perfect if you're watching your carb intake.
- Versatile- Suitable for vegetarians and meat-lovers alike, offering options for customization with different fillings.
- Easy to prepare- This light dish is the perfect weeknight meal, with simple ingredients and minimal prep time.
- Family-friendly- This spaghetti squash bake is a hit with both kids and adults.
- Make-ahead- Can be made ahead of time and reheated for a convenient meal on weeknights. It's also perfect for potlucks.
Ingredients
Ingredient notes and substitutions. See recipe card at the end of the post for full recipe details.
- Spaghetti squash- use a large squash, around 3 ½ pounds
- Marinara sauce- I use my favorite jarred marinara sauce to save time. If you want to make homemade sauce, try my the sauce in my spaghetti and meatballs recipe.
- Ricotta cheese- I use part-skim ricotta for a creamy filling
- Egg- holds the filling together
- Spinach- I like to add spinach to the filling. Use a package of frozen spinach to make prep a lot easier. You can use fresh spinach but be sure to cook it and squeeze out all of the liquid before adding it to the filling.
- Cheese- I use a mixture of mozzarella cheese and parmesan cheese in the casserole filling and on top.
How to Make Spaghetti Squash Lasagna Casserole Step-by-Step:
See recipe card at the end of the post for full recipe details.
1. Cook The Spaghetti Squash
First, you'll need to cook the spaghetti squash. The best way to do this is in the oven on a prepared baking sheet or in the air fryer. For more details, read my post on how to bake a whole spaghetti squash. To cook it in the air fryer, read my post on air fryer spaghetti squash. You can even cook it in the microwave.
2. Make The Filling and Assemble The Casserole
- Step 1- Prepare the casserole filling. In a large mixing bowl, mix ricotta cheese, egg, spinach, ยฝ cup mozzarella cheese, salt, and pepper.
- Step 2- Squeeze any excess liquid from the cooked spaghetti squash and add it to the bowl. Mix it all together.
- Step 3- To assemble the spaghetti squash lasagna, spread a thin layer of tomato sauce on the bottom of an 8x11-inch baking dish. Next, spread half of the squash and ricotta mixture on top.
- Step 4- Spread half of the remaining tomato sauce on top of the squash. Then, top with another layer of squash and another layer of tomato sauce. Finally, sprinkle mozzarella and Parmigiano cheese on top.
Bake the spaghetti squash lasagna casserole in the oven at 375°F for 35-40 minutes until bubbly and golden brown. Let it rest for 10 minutes before serving.
Chef's Tips:
- I use spinach in the filling of this vegetarian spaghetti squash recipe but you can add other veggies like bell peppers or mushrooms for a meaty texture
- If you are not trying to keep this dish vegetarian, you can add ground turkey, beef or Italian sausage to this spaghetti squash lasagna.
- You can use your favorite jarred marinara sauce or make homemade tomato sauce, if you have more time.
- Add your favorite seasonings to bump up the flavors in this dish like chili flakes, Italian seasoning or fresh herbs like parsley or basil.
- Make this casserole ahead of time and refrigerate or freeze it for a convenient weeknight meal.
- For more details on how to cook spaghetti squash, read my post on how to bake a whole spaghetti squash in the oven. To cook it in the air fryer, read my post on air fryer spaghetti squash.
How To Serve This Dish
This creamy spaghetti squash lasagna casserole can be the star of your meal. It can be paired with a side salad, garlic bread or other crusty bread for a satisfying yet light dinner. For a low-carb side dish option, try my cheesy cauliflower bread.
You can also serve this casserole as a hearty side dish alongside your favorite protein, such as chicken or seafood. Its creamy texture and rich flavors complement a wide range of main courses. It's equally suitable for weeknight family dinners or for your holiday table.
Recipe FAQs
Yes, you can! Be sure to let it cool completely. Then, wrap it tightly in plastic wrap. It will keep for up to three months in the freezer. To reheat, remove plastic wrap and heat in a 375°F oven until warmed through and bubbling.
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Recipe
Spaghetti Squash Lasagna Casserole
Equipment
Ingredients
- 1 large spaghetti squash (about 3 ½ pounds)
- 1 teaspoon olive oil
- 1 container (15 ounces) part-skim ricotta cheese
- 1 large egg
- 5 ounces frozen chopped spinach, defrosted and squeezed dry
- 1 ยฝ cups part-skim shredded mozzarella cheese, divided use
- 1 teaspoons salt
- ยผ teaspoon black pepper
- 1 jar (24 oz) jarred marinara sauce, like Rao's
- โ cup grated Parmigiano-Reggiano cheese
- fresh parsley or basil for garnish, optional
Instructions
- Preheat oven to 400°F. Cut the squash in half lengthwise and remove the seeds. Brush the flesh with 1 teaspoon oil. Place squash halves cut side down on a baking sheet lined with parchment paper. Roast in the oven until tender, about 40-45 minutes. Remove from oven and cool. When the squash is cooled, scrape the flesh with a fork so that it forms spaghetti-like strands. You should have a total of about 6 cups total. Alternatively, you can cook the spaghetti squash in the air fryer.
- Mix the ricotta, egg, spinach, ½ cup mozzarella cheese, salt, and pepper together in a large bowl. Squeeze all of the liquid from the spaghetti squash and add it to the bowl (the squash releases a lot of water as it cooks so make sure to squeeze it well). Stir to combine all of the ingredients.
- Turn the heat on the oven down to 375°F. To assemble the lasagna, spread a thin layer of tomato sauce on the bottom of an 8x11-inch baking dish. Next, spread half of the squash and ricotta mixture on top. Spread half of the remaining tomato sauce on top of the squash. Then, top with another layer of squash and another layer of tomato sauce. Finally, sprinkle the remaining 1 cup of mozzarella and the Parmigiano cheese on top.
- Bake in the oven 35-40 minutes until bubbly and cheese is melted. Garnish with parsley. Let stand 10 minutes before cutting and serving.
Notes
- I use spinach in the filling of this vegetarian spaghetti squash recipe but you can add other veggies like bell peppers or mushrooms for a meaty texture
- If you are not trying to keep this dish vegetarian, you can add ground turkey, beef or Italian sausage to this spaghetti squash lasagna.
- You can use your favorite jarred marinara sauce or make homemade tomato sauce, if you have more time.
- Add your favorite seasonings to bump up the flavors in this dish like chili flakes, Italian seasoning or fresh herbs like parsley or basil.
- Make this casserole ahead of time and refrigerate or freeze it for a convenient weeknight meal.
- For more details on how to cook spaghetti squash, read my post on how to bake a whole spaghetti squash in the oven. To cook it in the air fryer, read my post on air fryer spaghetti squash.
Frank Favorito says
Love the concept but it's more like baked spaghetti than a lasagne. I love squash of all kinds and the addition of spiralized zucchini added great color. I've grilled spaghetti squash, then shredded it, added Italian sausage, mozzarella, parm, chopped button mushroom, and some sauce. Covered with tin foil, return to the grill for 15 min, just enough to melt the cheese, serve and enjoy.
plasterers bristol says
Great recipe this, one of my favorites. thanks for sharing.Simon
Anonymous says
Just another note: This tastes even better the next day!
sonaliruder says
Yay, so glad to hear it! Thanks for sharing ๐
Kelley @ Chef Savvy says
This spaghetti squash looks amazing! Love that it is healthy and delicious!
sonaliruder says
Thanks for stopping by, Kelley!
Anonymous says
Made this today and it was pretty good. Next time I will add some fresh basil to the cheese mixture, and will use Costco's white linen marinara sauce instead of the crushed tomatoes (less acidic). I wouldn't try to pass it off as lasagna for guests, but it's great for my family trying to eat healthy and low carb!
sonaliruder says
Fresh basil sounds like a great addition and of course you can substitute your favorite jarred tomato sauce. I've also done that when I'm pressed for time. Thanks for trying out the recipe!
nutritionalanatalie.com says
I absolutely love this idea! My family does lasagna every Christmas, and this is a way to make it lighter and add some veggies. Great idea.
sonaliruder says
It's definitely a great way to add some veggies and cut some calories! Thanks for stopping by ๐
Cakespy says
Beautiful. I love spaghetti squash served pasta-esque but had never thought to lasagne-ify it!
sonaliruder says
Thanks! I'm going to start using that word- "lasagne-ify!" ๐
Jennifer Lynn-Pullman says
I just had spaghetti squash for the first time recently and loved it.
sonaliruder says
It's so good, right? Thanks for stopping by Jennifer!
Anonymous says
Awesome post! Looks delicious!
sonaliruder says
Thanks for stopping by!
Katie (The Muffin Myth) says
This looks so great! Light, healthy, and delicious! And as it happens, I've got a nice big spaghetti squash sitting on my counter right now, so I'm thinking this could be dinner this weekend. Funny, I was looking at Recipe Redux just the other day and thinking of applying. I think you've inspired me to go for it!
sonaliruder says
You should definitely go for it, it's such a wonderful group! I hope you enjoy the recipe if you go ahead and try it. Thanks Katie!
Mira Cookinglsl says
I love the healthy resuscitation of lasagna! Perfect idea to use spaghetti squash! Pinning and will give the recipe a try soon!
sonaliruder says
Thanks Mira! I really hope you enjoy it if you go ahead and try it out ๐
Erin says
I'm new to Recipe Redux also! I am so glad to join such a wonderful community all working towards the same goal! ๐ This recipe looks delicious! I have never used spaghetti squash in lasagna, but what a clever idea! I will have to give this a go...after I recover from Thanksgiving, of course! ๐
sonaliruder says
Thank you and welcome aboard too, it really is such a great community! Have a wonderful holiday!