With perfectly tender roasted squash and a creamy homemade alfredo sauce, this Spaghetti Squash Alfredo is an easy keto recipe that is great as a side or main vegetarian meal everyone will love!
Keto Spaghetti Squash Alfredo
We are a pasta-loving, carb-consuming family and people who say that spaghetti squash is as good as a bowl of fresh creamy pasta are liars. Lol. BUT we also love squash. Roasted spaghetti squash is a great healthy alternative to traditional spaghetti pasta if you’re looking to cut back on calories and carbs. It can be packed with flavor when seasoned properly and served with a delicious sauce.
I often make roasted spaghetti squash as a side but it also works well as a main dish, too, when combined with one of my other favorite things – alfredo sauce. Perfectly roasted spaghetti squash + homemade alfredo sauce = a super yummy, keto meal that everyone is going to love. You can’t go wrong serving this up for dinner!
This easy spaghetti squash with alfredo sauce recipe is made with just a few ingredients and a handful of seasonings.
(Scroll below to the printable recipe card for details and measurements.)
- Spaghetti squash – You’ll want a squash that’s approximately 3 pounds for this recipe.
- Heavy whipped cream – Gives the sauce a rich, creamy texture.
- Unsalted butter – If using salted butter, I recommended omitting the additional salt until you’ve tasted the sauce and then add extra, if necessary.
- Garlic – We love a mix of garlic powder and fresh garlic. If you want a more subtle garlic flavor, you could cut back on one or the other.
- Seasonings – A mixture of Italian seasoning, salt and black pepper, red pepper flakes, and nutmeg are added to the sauce for flavor.
- Parmesan cheese – For optimal results, use real Parmigiano-Reggiano right off the block.
- Chopped parsley & lemon wedges – For serving.
How to Roast Spaghetti Squash
For a full rundown, check out my post on how to cook spaghetti squash, but here’s a quick summary:
- Clean and pierce. Make sure to scrub the squash clean and dry it. Then piece the squash all over with a sharp knife.
- Roast. Transfer the squash to a baking sheet. Roast in an oven preheated to 400 degrees F. Roast until the squash is tender. This will depend on the size of the squash but typically takes about 1 hour for a 3 pound squash. You can poke it with a knife to make sure it’s tender. Be sure not to over cook it or it can become mushy.
- Let cool. Once the squash is cool enough to handle, cut it in half lengthwise. Discard the seeds and pulp. Use a fork to scrape the rest of the squash to get long strands (like spaghetti, hence the name).
How to Make Spaghetti Squash Alfredo
This spaghetti squash recipe is easy to make and once the squash has been roasted, it comes together in just 20 minutes or so.
(Scroll below to the printable recipe card for details and measurements.)
- Roast the squash. Roast the spaghetti squash as described above. Once you scrape the squash, keep it warm in a bowl.
- Make the alfredo sauce. Whisk the butter and cream over medium-low heat until the butter has melted. Add the garlic and other seasonings. Bring to a gentle simmer, whisking constantly, for 3 to 5 minutes. It should begin to thicken. Add the parmesan cheese and stir until melted and the sauce is smooth.
- Serve. Plate the spaghetti squash then spoon the alfredo sauce over the top. Garnish with black pepper and chopped parsley. Serve with lemon wedges.
Tips & Variations
Ensure perfectly cooked squash and creamy alfredo sauce with these tips. Plus a few ways to customize the recipe to your taste.
- Don’t overcook the spaghetti squash. Roast the spaghetti squash until tender but don’t overcook. You want the squash to have an al dente texture and cooking it for too long can make it mushy.
- Don’t boil the sauce. When making the alfredo sauce, be sure to keep it at a gentle simmer. It will curdle if you bring it to a boil.
- Be sure to whisk the sauce constantly. If you stop whisking you run the risk of the sauce sticking and burning.
- Add some protein. Feel free to add in some cooked chicken, shrimp, or bacon for a heartier meal.
- Switch up the sauce. Not a fan of alfredo sauce? You can serve spaghetti squash with any sauce you would make spaghetti with, like spaghetti sauce or marinara sauce.
Spaghetti squash alfredo makes a great low-carb, keto dinner all on its own. I like to top mine with a bit of cracked black pepper and chopped parsley, then squeeze a bit of lemon over the top to bring it all together. So good!
If you prefer a heartier dinner, you can easily add your favorite protein like cooked chicken, shrimp, or bacon. And nothing pairs together quite like pasta and salad, so feel free to start your dinner with a simple side salad. If you’re not aiming for keto or low carb, you can’t go wrong with garlic bread either.
How to Store & Reheat Leftovers
- How long does spaghetti squash last? Cooked spaghetti squash will last for up to 4 days when stored in the fridge.
- How to store leftovers. You can store the spaghetti squash and alfredo sauce together or separately in the fridge for 4 days in tightly sealed containers.
- How to reheat leftovers. Leftovers can be gently reheated in the microwave or on the stovetop.
More Alfredo Recipes:
- Chicken Alfredo Pizza
- Chicken Alfredo Lasagna Rolls
- Homemade Alfredo Sauce
- The best Chicken Alfredo
- Chicken Alfredo Tortellini Soup
- Chicken Alfredo Bake
I hope you love this delicious and easy recipe – be sure to give it a review below! Also don’t forget to follow Belly Full on TikTok, Facebook, Instagram, Pinterest, and YouTube!
Spaghetti Squash Alfredo
- 3 pound spaghetti squash , cleaned and dried
- 1 cup heavy whipping cream
- 1/4 cup unsalted butter , cut into cubes
- 2 cloves garlic , minced
- 1/4 teaspoon garlic powder
- 1/4 teaspoon Italian seasoning
- 1/4 teaspoon coarse salt
- 1/4 teaspoon cracked black pepper
- 1/8 teaspoon crushed red pepper flakes
- pinch of nutmeg
- 1 1/2 cups freshly grated Parmesan cheese
- 1 tablespoon chopped parsley , for garnish
- lemon wedges , for serving
Roast the squash
- Preheat oven to 400 degrees F.
- Pierce squash a few times all over with a sharp knife, then transfer to a baking sheet.
- Roast until tender (usually 1 hour for a 3 pound squash for al dente strands, which is what you want. Roast too long and it could get mushy.) Then let cool for 15 minutes.
- Once squash is cool enough to handle, cut in half, lengthwise. Remove and discard the seeds and pulp.
- Using a fork, scrape the rest of the squash to get long strands (like spaghetti.) Place in a bowl and keep warm.
Make the Alfredo Sauce
- In a large nonstick saucepan, add the cream and butter over medium-low heat; whisk until butter has melted.
- Add in the minced garlic and all the seasonings; whisk until combined and smooth.
- Bump up the heat slightly and bring to a gentle simmer (do not boil) and cook for 3-5 minutes, whisking constantly, until it starts to thicken and has reduced a bit. (Make sure your sauce isn’t boiling or it will curdle, and don’t stop whisking or you run the risk of the sauce sticking and burning.)
- Stir in the parmesan cheese just until melted and the sauce is smooth.
- Divide squash among bowls or plates. Spoon Alfredo sauce evenly over the tops. Garnish with a couple turns of fresh cracked black pepper, some chopped parsley, and serve with lemon wedges.
- Enjoy warm!