Creamy Spinach Spaghetti Squash Casserole

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Creamy Spinach & Spaghetti Squash Bake | Life, Love, and Good Food

This creamy Spaghetti Squash Casserole is a cheesy vegetarian, keto-friendly, low-carb, gluten-free casserole. That covers just about all the bases!

Looking for more vegetarian main dishes? My Easy Skillet Vegetable Lasagna is loaded with zucchini, yellow squash, onions, and mushrooms and is ready in just 30 minutes! Or, you may like this Healthy Butternut Squash Soup — it’s perfectly creamy and delicious. 

Ingredient notes

  • Spaghetti squash — Choose a squash that doesn’t have cracks or spots on its skin and be sure the stem is not withered and dry.
  • Red bell pepper — Any color bell pepper will work, but I like the sweetness of red bell peppers.
  • Onion — A yellow or sweet onion along with fresh garlic adds the aromatic flavors to this dish. To make it heartier, toss in mushrooms, sundried tomatoes, or any other veggie you find in your fridge.
  • Spinach — I use fresh baby spinach, but you can also use frozen chopped spinach. Just be sure to thaw and squeeze out any liquid before adding to the casserole.

Wow! This is AWESOME! I’ve been on a ketogenic diet for a few months, and this meal just hits the spot and tastes so indulgent! Thank you for sharing this!

— Kim

How to make this easy recipe for spaghetti squash

STEP 1 | Cook the squash

Cut the spaghetti squash in half length-wise and use a large spoon to scrape and scoop out the seeds.

Lay the squash cut side down in a baking dish and pour in 1/2 cup water, then bake the squash until it is tender and can easily be pierced with a fork.

Remove the squash from the pan and let rest. Once it is cool enough to handle, gently scrape all the flesh away from the rind/peel with a fork.

Spaghetti squash on a wooden table, with fork and frying pan

STEP 2 | Sauté vegetables

Sauté diced onions and red bell pepper until tender, then add minced garlic and cook another minute until fragrant.

Toss in fresh spinach and cook until wilted.

STEP 3 | Add cheese and bake

Add a block of softened cream cheese to the pan with the veggies and stir until melted.

Gently stir in the spaghetti squash and transfer the mixture in a lightly greased casserole dish.

Top with mozzarella and parmesan cheese and bake until hot, bubbly, and the cheese has a golden crust.


  • Cook spaghetti squash in the instant pot – Add one inch of water to the Instant Pot and insert the steamer basket. Lay the squash in the basket (not in the water) and lock the lid with the valve set to vent. Pressure cook for 5 minutes, then quick release the steam by carefully opening the vent. Remove the squash and let cool.
  • After removing the casserole from the oven, allow it to set for at least 15 minutes. Then, you’ll be able to cut it into squares and serve like a lasagna.
Creamy Spinach & Spaghetti Squash Bake | Life, Love, and Good Food

Frequently asked questions

How do you reheat spaghetti squash casserole?

To reheat the casserole, place a serving on a microwave-safe plate and heat for 1 1/2 minutes in the microwave until warmed through.

Can I add meat to this casserole?

To serve spaghetti squash casserole as a more complete meal, add cooked and crumbled Italian sausage or shredded rotisserie chicken before you bake. Both are delicious options!

More delicious vegetable recipes

Creamy Spinach & Spaghetti Squash Bake | Life, Love, and Good Food

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A serving of spinach spaghetti squash casserole on a blue plate with a fork

Creamy Spinach Spaghetti Squash Casserole

Creamy Spinach & Spaghetti Squash Bake with sautéed spinach, red pepper, garlic, and three kinds of cheese. Keto-friendly recipe, too!
4.54 from 110 votes
Prep Time 30 minutes
Cook Time 30 minutes
Total Time 1 hour
Course Vegetables & Sides
Cuisine American
Servings 8 servings
Calories 229 kcal


  • 1 3 lb. spaghetti squash
  • ½ cup water
  • 1 teaspoon olive oil
  • ½ large red bell pepper diced
  • ½ cup diced sweet onion
  • 1 clove garlic minced
  • 4 cups spinach chopped
  • dash of nutmeg
  • 1 teaspoon salt
  • ½ teaspoon pepper
  • 8 oz. cream cheese softened
  • 1 cup mozzarella cheese
  • ¼ cup parmesan cheese


  • Preheat oven to 400 degrees.
  • Slice spaghetti squash in half length-wise. Scoop out seeds and place cut side down in a glass baking dish. Pour 1/2 cup water into dish and bake for about 30-35 minutes. With a fork gently shred the pulp from the inside of the squash and set aside.Reduce oven heat to 375 degrees.
  • On top of stove, heat olive oil in a large skillet over medium heat. Add the onion and red bell pepper. Sauté about 5 minutes, until tender. Add the garlic and cook until fragrant, about 1 minute.
  • Add the spinach to the skillet and season with the nutmeg, salt, and pepper. Cook and stir until the spinach is wilted.
  • Gently stir in the cream cheese until melted. Add the spaghetti squash and stir until combined.
  • Pour the mixture into a casserole dish that is lightly coated with cooking spray. Top with the mozzarella and parmesan cheese. Bake at 375 degrees for 30 minutes, or until bubbly and cheese is lightly browned.



  • After removing the casserole from the oven, allow it to set for at least 15 minutes if you’d like to cut it into squares to serve like lasagna.
  • To reheat the casserole, place a serving on a microwave-safe plate and heat for 1-1/2 minutes in the microwave.
To cook the spaghetti squash in an instant pot:
  1. Cut the spaghetti squash in half length-wise.
  2. Use a large spoon to scrape and scoop out the seeds.
  3. Add one inch of water to the Instant Pot and insert the steamer basket.
  4. Lay the squash in the basket (not in the water) and lock the lid and turn the valve to vent.
  5. Pressure cook for 5 minutes. When the pot beeps, hit cancel.
  6. Quick release the steam by carefully opening the vent.
  7. Remove squash and allow it to cool enough to handle.
  8. Use a fork to gently scrape all the flesh away from the rind/peel.


Serving: 1gCalories: 229kcalCarbohydrates: 17gProtein: 10gFat: 15gSaturated Fat: 8gPolyunsaturated Fat: 5gCholesterol: 42mgSodium: 592mgFiber: 5gSugar: 6g

Life Love and Good Food does not claim to be a registered dietician or nutritionist. Nutritional information shared on this site is only an estimate. We recommend running the ingredients through an online nutritional calculator if you need to verify any information.

Keyword spaghetti, spinach, squash
Tried this recipe?Let us know how it was.

Beyond the recipe

Confession time. The first time I made this recipe was my very first experience cooking spaghetti squash. Truth! I’m not sure why it’s took me so long to try this vegetable, but let me tell you that this first time will not be my last.

Unlike other veggies that you spiralize to make noodles, once cooked the flesh of a spaghetti squash can be separated into spaghetti-like strands (or squaghetti as I like to call it) simply by scraping it out with a fork.

One three-pound squash will make enough squaghetti to equal around a pound of pasta noodles — a great alternative when you are watching your carb intake!

Sheila Thigpen, blogger

About Sheila Thigpen

Recipe Developer, Food Photographer, Food Writer

Sheila Thigpen is the publisher of Life, Love, and Good Food — a Southern food blog — and the author of Easy Chicken Cookbook and The 5-Ingredient Fresh and Easy Cookbook. After 20+ years in the publishing industry, she retired in 2018 to focus on her own creative endeavors full time. She and her husband live near the beautiful Smoky Mountains and have a precious little granddaughter who has stolen their hearts. As an influencer, Sheila has collaborated with brands like Creamette, Kroger, HERSHEY’S, Hamilton Beach, Garafalo Pasta, OXO, Smithfield, Valley Fig Growers, and more.

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  1. Really enjoyed this recipe, and will make again. I didn’t have spinach on hand, so I used fresh broccoli. I parboiled it for just 3minutes and then added it to the cheese moisture. Next time I might add pine nuts!

  2. 2 stars
    Made half a recipe. Followed exactly. All I could taste was cream cheese. The nutmeg added nothing. It was actually better the next day as a leftover, especially after I mixed the cheese from the topping in with the spaghetti squash. I do think this one has possibilities, so I am going to try it again with modifications – mixing cheese with the cream cheese initially and replacing the nutmeg with something else (& maybe several other things)

  3. 5 stars
    I was looking for something a bit different. It’s just 2 of us so I quartered the recipe. It worked out great! I tossed in a few cherry tomatoes, halved. They added just the right flavor.

  4. This recipe is a real keeper!!
    So full of flavor and so versatile, you can add meat of your choice or leave it as is for vegetarian version.
    Top notch, we love it. Thank you for posting it for all to enjoy

  5. 5 stars
    This dish was so good. I ate it for days. I did half the cream cheese and it was perfect for my family. My daughter was surprised that this qualified as her veggies. We’ll definitely be making it again.

4.54 from 110 votes (93 ratings without comment)

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