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.
You didn’t list cream cheese in the ingredients. How much?
I’m so sorry cream cheese was listed in the recipe instructions! I tested the recipe with cream cheese initially and decided to thicken the sauce by adding more shredded cheese instead (it’s better this way, I promise!)
Hope you enjoy and thanks for pointing out that type!
Hi
I would like to verify that this recipe have cream cheese in it. The list of ingredients doesn’t list cream Cheese however the list of instructions mentions in step 0.
Thanks
Hi Debbie! Thanks for pointing out that cream cheese was listed in the recipe instructions! I tested the recipe with cream cheese initially and decided to thicken the sauce by adding more shredded cheese instead ( I promise it’s better this way!) Hope you enjoy!
I know my wife would love this recipe! because she’s basically been obsessed with using squash in every recipe she makes lately haha thank you, great recipe!
Super recipe, can be cooked with courgette too
Thank you!
Thanks for the suggestion 🙂 Glad you enjoyed! 🙂
This is so delicious. Love the bite the squash gives. Made this the other night. Did not have Gruyere but used a Colby/cheddar blend. Can’t wait to taste with the Gruyere I also added a touch of dry mustard.
LOVE IT! I’m happy you enjoyed, thanks for sharing your tweaks Missy!?
This was enjoyed by my entire family and friends of my kids. I would say this could be a low carb lasagna replacement….the flavor was amazing. I am washing an empty pan to prove it, as well as requests to please make it again.
Yay! SO glad everybody enjoyed it, Mary! 🥰
My husband does not typically like spaghetti squash, but he loved this. I used cream cheese. The only thing I swapped was the sausage. I substituted one pound of ground lamb instead and added spices that go well with lamb. It was fantastic! We put six servings in the freezer and that is the other thing I love about this recipe. Once it cools, it cuts into pieces very nicely and freezes well. Thanks
Sounds really good, Wendy! SO glad you loved it!
This is delicious! It doesn’t feel low carb at all.
Yay! SO glad you liked it, Amanda!
I love this recipe. The flavors are delicious, and using spaghetti squash in place of noodles is genius! I really enjoyed this one.
SO glad you enjoyed, Beth!
So perfect for dinner! Great take on spaghetti squash.
Yahoo! SO glad you liked it, Erik!
What a great recipe! So hungry for this!
Thank you, Erin! Hope you enjoy!
Oh boy , this looks terrific! My family would LOVE it!!
Yay! Can’t wait to hear what they think, Katerina!
The perfect weeknight meal! I love that its keto!!
Right?! Hope you enjoy, Beti!
So creamy and cheesy, also super filling. We didn’t miss the pasta at all!
Right?! SO glad you liked it, Krystle!
This was awesome! Perfect comfort food on a snowy-blowy day! It firmed up beautifully after it cooled and was so easy to cut into servings to freeze for later. I will definitely make this again! YUM!
Yay! So glad you loved it!
I will be making this for the next family get together! It looks fantastic.
Yahoo! 🥳 Can’t wait to hear what everyone thinks, Amanda!
Such an amazing dish! I would love to make this!
Hi, Erin! 🥰 Can’t wait to hear what you think!
Mmmmm…. it looks amazingly delicious! Great idea for the Sunday family dinner!
Can’t agree with you more, Catalina! 🥰
I’m definitely going to have to try this recipe!
So excited! 🥰 Can’t wait to hear what you think, Sandra!
Super tasty! Whole family loved this for dinner
Yay! 🥰 SO glad everyone loved it!!