Cheesy, and aromatic, with a delicious cream sauce, this spaghetti squash casserole is the perfect comfort food to serve on a cozy night in. Great to feed a family or for meal prep. This dish will make you fall in love with spaghetti squash–if you haven’t already.
Is Spaghetti Squash Casserole Keto? Low Carb? Paleo? Gluten Free?
This keto spaghetti squash is made entirely of low carb ingredients, making it great for those following a low carb or keto eating plan. It’s not paleo, due to the cheese, cottage cheese, and cream cheese. Thanks to spaghetti squash, this dish is totally gluten free!
Spaghetti Squash? As a Pasta Substitute?
Spaghetti squash is my favorite pasta substitute. With minimal carbs (unlike butternut squash noodles), a great texture (unlike shirataki noodles), and a subtle taste.
Plus it comes together easily (unlike almond flour pasta) and can cook for long periods of time without getting soggy (unlike zucchini noodles).
- Taste: VERY subtle, just like pasta.
- Texture: Depending on how long you bake it, spaghetti squash can have a slight crunch. Obviously, the more you cook it, the softer it will be. We like our spaghetti squash al dente to prevent mush.
- Carbs: Spaghetti squash has 4.2 g of net carbs per cup.
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Ingredients You’ll Need
Have you had million-dollar spaghetti before? It’s absolutely to die for. This recipe is based on my Mom’s version, and our whole family liked this spaghetti squash variation just as much. Here are some ingredient notes:
- Spaghetti Squash – 1 large or 2 small. The trick here is to get exactly 4 pounds of squash, otherwise, the noodle-to-sauce ratio will be off, and that’d be a very sad thing.
- Italian Sausage – can’t find Italian sausage without casing? Just use a sharp knife to cut the casing, and squeeze out the meat. I prefer sweet sausage for this spaghetti squash casserole, feel free to use spicy if that’s more your thing.
- Keto Spaghetti Sauce – storebought spaghetti sauce is often loaded with added sugar. I love making my own, or, Kroger’s “Simple Truth” is a great sugar-free option.
- Cottage Cheese or Ricotta Cheese – I prefer cottage cheese for the added protein.
- Cream Cheese – leave it on the counter for a few so it’s nice, soft, and easy to incorporate.
How To Cut + Cook Spaghetti Squash
Cutting spaghetti squash is typically the hardest step to prepping this veggie. If you run into trouble you can always do as I did below:
- Remove the top of the squash with the stem (removing the stem makes it easier to slice).
- Slice the squash through the center.
- Scoop with a spoon to remove the seeds.
- Bake it cut side down on a baking sheet until the “noodles” shred easily.
You can also microwave your squash.
This is the absolute easiest way to cook spaghetti squash. And, you don’t have to deal with that tough stem. To do this:
- Pierce the squash all over with a fork, keeping the squash whole.
- Microwave for 5 minutes. Flip, repeat. Then let it sit for 5 minutes before slicing it in half.
- Scoop out the seeds + discard them.
- Shred with a fork.
How to Make Spaghetti Squash Casserole
Not much to this spaghetti squash casserole, here’s your step-by-step guide:
Slice, cook, and shred spaghetti squash (tips above). Saute onion and garlic. Add sausage and brown. Add marinara and spaghetti squash and stir to combine.
Combine cottage or ricotta cheese, cream cheese, sour cream, 1 cup of mozzarella, and Italian seasoning.
Place a layer of spaghetti squash in the baking dish. Then cheese combo. Then remaining spaghetti squash. Top with cheese. Bake + enjoy.
Tweaks + Variations
This spaghetti squash casserole is easy to add your spin to. Here are a few ideas for you:
- Add more veggies. Subtle-tasting vegetables would be great here. Just saute first to cook out their liquid. Think mushrooms, kale, or spinach.
- Swap the protein: Skip Italian sausage and add shredded chicken, ground beef, or even keto meatballs, such as my mozzarella stuffed meatballs.
- Or skip the meat, for a vegetarian dish. You could turn this into a vegan casserole by replacing all cheese and dairy products with your favorite substitutes.
- Make stuffed spaghetti squash boats instead of placing this in a casserole dish.
- Try a different sauce, like keto alfredo (obviously skip the sour cream and cottage cheese), or any other pasta sauce.
Storing, Reheating, and Freezing Tips
Spaghetti squash will release liquid as it rests in the fridge. So, after reheating a slice in the microwave, simply toss everything to reincorporate the liquid into the cheese and sauce. It won’t taste any different than freshly baked spaghetti squash casserole.
I don’t like freezing this casserole due to the amount of water in squash.
More Pasta Swaps to Love
- Cauliflower Lasagna
- Shrimp Carbonara
- Cabbage Lasagna
- Cauliflower Mac and Cheese
- Eggplant Lasagna
- Zoodle Salad
Spaghetti Squash Casserole
Print Recipe Pin RecipeIngredients
- 1 large spaghetti squash roughly 4 pounds (note 1)
- 2 tablespoons olive oil
- 1 cup yellow onion chopped
- 4 cloves garlic minced
- 1 pounds Italian sausage casings removed (note 2)
- 2, 24 ounce jars Keto Spaghetti Sauce (note 3)
- 8 ounces cottage cheese or ricotta cheese (note 4)
- 8 ounces cream cheese softened
- 1/4 cup sour cream
- 1 tablespoon Italian seasoning
- 3 cups mozzarella shredded + divided
- salt
- pepper
- Fresh basil
Instructions
- Prep. Preheat oven to 350F and line a baking sheet with parchment paper.
- Spaghetti squash. Slice the spaghetti squash (1) in half, and scoop out seeds and fiber with a spoon. Place cut side down on the prepared baking sheet, and bake in the preheated oven for 1 hour, or until the flesh is fork-tender. Set aside, and allow squash to cool for 10 minutes before shredding with a fork into spaghetti. Place cooked spaghetti squash in clean kitchen towels, and ring out any additional liquid.
- Sauce. Meanwhile, in a large skillet, heat olive oil (2 tablespoons) over medium heat. Add the onion (1 cup) and saute until softened, about 5 minutes. Add the garlic (4 cloves) and cook until fragrant, about 2 minutes. Add sausage (1 pound), and crumble into small pieces using the back of your spoon as it browns. Cook until no longer pink, then remove pan from heat. Push the meat and veggies to one side of the pan, then tilt the pan to the opposite side so the grease pools. Use tongs and paper towels to sop up extra grease. Add marinara and shredded spaghetti squash to the skillet and stir to combine. Set skillet aside.
- Cheese combo. In a medium bowl, combine cottage or ricotta cheese (8 ounces), cream cheese (8 ounces), sour cream (1/4 cup), 1 cup of mozzarella, and Italian seasoning (1 tablespoon).
- Assemble. Layer half the spaghetti squash along the bottom of the baking dish, followed by the entire bowl of cheese mixture, then the rest of the spaghetti squash and sauce (2, 24 ouce jars). Top with the remaining 2 cups of mozzarella.
- Bake + enjoy! Bake casserole in preheated oven for 35-45 minutes, or until it's heated through and the cheese in melted. Serve with fresh basil slices and enjoy!
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Lindsey’s Tips
- Spaghetti Squash – You want exactly 4 pounds of squash for the optimal noodle to sauce ratio. This should be about 1 large or 2 small.
- Italian Sausage – can’t find Italian sausage without casing? Just use a sharp knife to cut the casing, and press out the meat from inside. I prefer sweet sausage for this keto spaghetti squash casserole, feel free to use spicy if that’s more your thing.
- Spaghetti Sauce – storebought sauces often contain added sugar. I love making my own, or, look for a sugar free jar
- Cottage Cheese or Ricotta Cheese – I prefer cottage cheese for the added protein.
- Nutritional information was calculated using cottage cheese, not ricotta cheese.
Veronica
This was amazing! My husband and I can’t stop talking about how great this was. I didn’t have mozzarella so I used parmesan it came out great! Thank you!
Lindsey
Yay! So glad you both enjoyed this, Veronica!
Amanda Batcher
We’re big fans of spaghetti squash, and this was a huge hit for our dinner!
Lindsey
Yay!! So glad you all loved it, Amanda!
Beth
That looks absolutely delicious. It’s such a great way to get all that spaghetti flavor and texture without the carbs.
Lindsey
Right?! Hope you enjoy, Beth!
Catalina
These spaghetti squash are so good! Now it’s on my keto menu! Yum!
Lindsey
Yay!! SO glad you liked them, Catalina!
Erin | Dinners, Dishes and Dessert
Looks incredibly delicious! I would love to make this!
Lindsey
Yay! Can’t wait to hear what you think, Erin!
katerina @ diethood.com
This sounds really, reaaally good!! I am so excited to give it a try!!
Lindsey
Yay!! Can’t wait to hear what you think, Katerina!
Sandra
This is seriously amazing!! My whole family really enjoyed it!
Lindsey
Yay!! So glad everyone liked it!
Sandra
This was a really huge hit at my house! I will definitely make it again! Thanks for the recipe!
Lindsey
Yay! So glad you all loved it, Sandra!
Allyson Zea
This looks SO delicious and flavorful!!
Lindsey
Can’t agree with you more, Allyson!