Baked Spaghetti Squash Alfredo is rich, creamy, cheesy, and low carb—what’s not to love?! This might just be my favorite way to use spaghetti squash.

Fork pulling baked spaghetti squash alfredo from casserole dish


Spaghetti squash Alfredo: the low-carb cousin of traditional Alfredo pasta. It’s got everything you love about the real deal, minus the fettuccine. But who needs noodles when you’ve got a luxurious cheesy creamy sauce?!

Real Alfredo sauce isn’t thickened with flour, so it’s low carb on its own. Which means to make a low carb version of the traditional dish, all we have to do is swap out the pasta. Spaghetti squash is up for the job!

Cook the squash until it’s tender and then shred it into noodle-like strands. Mix it with the rich, creamy Alfredo sauce, stuff it back into the hollowed out spaghetti squash, and broil it until the top is browned in spots and the sauce is bubbly.

Even if you’re not following a low-carb or keto diet, you’re going to flip for this baked spaghetti squash Alfredo recipe, I promise!

Fork shredding spaghetti squash

Ingredients for Baked Spaghetti Squash Alfredo

Here’s a quick rundown of what you’ll need for this recipe. For the full measurements, scroll down to the recipe card.

  • Spaghetti Squash – Learn more about how to cook spaghetti squash in the oven.
  • Olive Oil – This helps the squash get a nice browning on the cut side.
  • Kosher Salt and Black Pepper – Always essential!

For the Sauce:

  • Salted Butter – The starting point of the sauce, and useful for getting a nice sear on the broccoli.
  • Broccoli Florets – Broccoli bulks up this baked spaghetti squash Alfredo to make it more substantive and satisfying.
  • Heavy Cream and Half-and-Half – All heavy cream would make the sauce a bit, well, heavy. That’s why I like to combine it with half-and-half.
  • Lemon – Fresh lemon juice and lemon zest to cut some of the richness.
  • Grated Parmesan Cheese – Freshly grated is important here! The pre-grated stuff won’t melt smoothly into the sauce.
  • Spinach – This wilts into the sauce, adding some nutrition without changing the flavor much.
  • Ground Nutmeg – Adds some cozy flavor to cream and cheese sauces. 
  • Kosher Salt and Ground Pepper – I like using a generous amount of freshly ground black pepper to make the flavor pop.
Overhead view of spaghetti squash alfredo mixture stuffed into squash shells
Overhead view of spaghetti squash alfredo in baking dish before baking
Overhead view of baked spaghetti squash alfredo in casserole dish

How to Make Baked Spaghetti Squash Alfredo

This is just a quick summary of the steps involved in making this recipe. When you’re ready to cook, print out the recipe card at the bottom of the post for full instructions!

  1. Roast the spaghetti squash. Halve it, scoop out the insides, brush with oil and season, then bake at 400ºF until it’s tender.
  2. Shred the squash. Use a fork to scrape the flesh, creating “spaghetti” strands. Transfer to a mixing bowl and season with salt and pepper.
  3. Cook the broccoli. Melt the butter in a pan over medium-heat. Cook the broccoli until it softens slightly.
  4. Simmer. Whisk in the cream and half-and-half. Reduce heat to low and simmer.
  5. Finish the sauce. Remove from heat. Whisk in the lemon juice and zest, then stir in the cheese, spinach, and nutmeg. Season to taste.
  6. Put it all together. Stir the spaghetti squash into the sauce, then divide the mixture into the hollowed out squash skins. Sprinkle cheese over the top.
  7. Bake. Place the spaghetti squash Alfredo boats in the oven and broil for 2 to 3 minutes. 
  8. Serve. Finish with additional Parmesan and basil, if desired, then serve.
Forkful of creamy baked spaghetti squash alfredo held over baking dish

Tips for Making Baked Spaghetti Squash Alfredo

This recipe is easy to make, but these tips will help you make sure it turns out absolutely perfect.

  • Try a different cooking method for the squash. While this recipe calls for baking the squash in the oven, you can also microwave spaghetti squash or cook spaghetti squash in an Instant Pot. Keep in mind that different cooking methods may result in slightly different textures.
  • Don’t overcook the squash. Make sure to check on your squash while it’s baking and avoid leaving it in the oven for too long. Overcooked spaghetti squash can become mushy and lose its strand-like texture!
  • Keep an eye on the squash while it broils. It can go from toasty to burnt very fast! 

Variations

  • Add chicken. You can stir pieces of Oven Baked Chicken Breast into the spaghetti squash mixture, or serve sliced Cast Iron Skillet Chicken Breast on top of the baked spaghetti squash Alfredo when it’s done cooking.
  • Try other vegetables. Swap the broccoli for mushrooms, try chard or kale instead of spinach, etc. Make this spaghetti squash Alfredo recipe your own!
  • Give it a breadcrumb topping. If you’re not concerned about this recipe being low-carb, stir together some panko with garlic powder, salt, pepper, and olive oil and sprinkle this mixture over the tops of the spaghetti squash boats before broiling.
Pulling forkful of baked spaghetti squash alfredo from baking dish

What to Serve With Baked Spaghetti Squash Alfredo

More Alfredo Recipes

Fork pulling baked spaghetti squash alfredo from casserole dish

Get the Recipe: Baked Spaghetti Squash Alfredo

Yield: 4 servings
Prep Time: 20 minutes
Cook Time: 55 minutes
Total Time: 1 hour 15 minutes
This baked spaghetti squash Alfredo is a low-carb version of the classic pasta dish, with a rich, creamy sauce and lots of cheese. So good!
5 from 2 votes
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Ingredients

  • 1 large spaghetti squash
  • 1 tablespoon olive oil
  • ¼ teaspoon kosher salt
  • Black Pepper, optional
  • For the sauce

For the sauce

  • 1 cup salted butter
  • 1 cup chopped broccoli florets
  • 2 cups heavy cream
  • 2 cups half and half
  • 3 tablespoons fresh lemon juice
  • 1 tablespoon fresh lemon zest
  • 4 cups freshly grated parmesan cheese
  • 1 cup chopped spinach
  • ½ teaspoon ground nutmeg
  • Kosher salt and fresh ground pepper to taste

Instructions 

  • Preheat oven to 400˚F and line a large baking sheet with parchment or foil.
  • Using a shark kitchen knife, cut the spaghetti squash in half lengthwise. If difficult to cut, poke a few holes with a fork into the skin and microwave for 3-4 minutes to soften.
  • Using a large spoon, scoop out the seeds and scrape away some of the stringy flesh.
  • Lightly brush the inside of the squash with the oil and sprinkle with salt. Place cut side down on the baking sheet and transfer to the oven.
  • Bake the squash for 45 minutes to 1 hour or until the insides can easily be shredded with a fork.
  • Allow squash to cool for about 15 minutes, before scraping the flesh out with a fork, making sure to keep the skin intact. Place squash in a mixing bowl, lightly season with salt and pepper and set aside.

For the sauce:

  • In a large saucepan, melt the butter over medium heat. Add the broccoli and cook for 2-3 minutes until bright green and starting to soften.
  • Whisk in the cream and half and half. Turn the heat to low and heat to a simmer.
  • Remove from the heat. Whisk in the lemon juice and zest.
  • Stir in the cheese 1 cup at a time, stirring until smooth.
  • Stir in the spinach and nutmeg. Season with salt and pepper, to taste.
  • Add spaghetti squash to the skillet and toss with the alfredo sauce and broccoli. Adjust seasonings and fill the hollowed squash skins with the mixture.
  • Sprinkle each stuffed squash with the cheese and return to the oven. Broil for 2-3 minutes until golden brown and bubbling.
  • Top with chopped fresh basil and parmesan cheese. Serve immediately.
Calories: 1482kcal, Carbohydrates: 31g, Protein: 46g, Fat: 134g, Saturated Fat: 82g, Polyunsaturated Fat: 6g, Monounsaturated Fat: 37g, Trans Fat: 2g, Cholesterol: 367mg, Sodium: 2273mg, Potassium: 768mg, Fiber: 5g, Sugar: 17g, Vitamin A: 5513IU, Vitamin C: 36mg, Calcium: 1483mg, Iron: 2mg
Author: Kellie
Course: Dinner, Main Course, vegetable
Cuisine: American, Italian