Spaghetti Squash Casserole with Sausage

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Baked spaghetti squash casserole with sausage is a versatile, healthy low carb comfort food dish that might just become your family's favorite weeknight meal!

Baked Spaghetti Squash Casserole with Sausage in a skillet with a striped napkin around the handle.

If you're like me and always looking for a healthy, delicious meal for your family that's also easy to prepare, then you're in the right place! This hearty spaghetti squash recipe is a low-carb casserole cooked and baked in a skillet, ensuring every bite is flavorful and clean up is a breeze. Serve this delectable spaghetti squash casserole with a side of garlic bread or a fresh green salad for a balanced meal.

Not only is this low carb casserole recipe delicious, it's also affordable to make. Spaghetti squash is relativity inexpensive at the grocery store, and the rest of the ingredients can easily be swapped out for what you have in your pantry. Also, if you have room for a garden, this is one of the easiest squashes to grow! We plant spaghetti squash seeds every year and always have a bumper crop!

Why You'll Love Spaghetti Squash Casserole with Sausage

Low-Carb Goodness: This healthy comfort food is made with spaghetti squash strands instead of traditional spaghetti noodles or regular pasta noodles so that you can indulge without the guilt!

Tasty: In my book, you can never go wrong with the combination of Italian sausage, mushrooms, onions and garlic! Toss in a few other simple ingredients like spinach, tomatoes and cheese, and you've got a comfort food high on taste and low on effort. Your whole family will love this spaghetti squash casserole recipe!

Versatile: Want to switch things up? You can easily modify this spaghetti squash and sausage casserole recipe to suit your taste buds. More on this later below.

Easy to Make: Even if you're a newbie in the kitchen, worry not! This spaghetti squash Italian sausage casserole is simple to whip up.

Great for Meal Prep: Make a large batch of sausage spaghetti squash bake, and you've got a ready-to-go meal for the next few days!

Ground Italian sausage, spaghetti squash strands, mushrooms, onions and garlic, diced tomatoes, Italian seasoning, Parmesan cheese, mozzarella cheese and spinach.

Ingredients Needed

spaghetti squash
Italian Sausage
onion
mushrooms
garlic
canned diced tomatoes
Italian seasoning
baby spinach
mozzarella cheese
Parmesan cheese

See the printable recipe card below for exact quantities.

How to Make Spaghetti Squash Casserole with Sausage

Spaghetti Squash Casserole with Sausage ingredients mixed together in a skillet with spatula.

Skillet sprinkled with cheese sprinkled on top.

Now, let's get down to the nitty-gritty of how to make this delightful dish. I promise it's as easy as pie...or, in this case, casserole!

Start by preheating your oven to 400°F and baking your spaghetti squash on a baking sheet. How to Roast Spaghetti Squash in the Oven.
While your squash cooks, cook the Italian sausage, mushrooms, onion and garlic in a large sauté pan over medium-high heat.
Once your squash is done, use a fork to scrape out the "spaghetti." Mix with the cooked sausage, onion, garlic, Italian seasoning, spinach and diced tomatoes.
Sprinkle with cheese and bake until bubbly and golden.

See the printable recipe card below for exact instructions.

And there you have it! A mouth-watering spaghetti squash casserole with sausage that's low in carbs and big on taste.

Ingredient Substitutions

Don't have diced tomatoes? Use 1 cup of tomato sauce or jarred marinara sauce. You could even use any type of pasta sauce you have in your pantry.

Don't have spinach? Use kale instead.

Don't have garlic to mince? Use ¼ teaspoon of garlic powder.

Don't have Italian sausage? Use turkey sausage, chicken sausage, regular ground sausage or ground beef.

Baked Spaghetti Squash Casserole with Sausage in a skillet with a wooden spoon and striped napkin around the handle.

Recipe Variations

This recipe is truly versatile!

Vegetarian Delight: Switch out the Italian sausage for a vegetarian substitute or go all in with a medley of veggies like bell peppers, zucchini and mushrooms for a meatless version that's just as satisfying.

Cheese Lovers: Can't get enough cheese? Try adding a mix of cheeses, such as gouda, cheddar and fontina, for a super cheesy spaghetti squash casserole. You could even add one cup of cottage cheese which would increase the protein and add tons of flavor!

Spice it Up: If you like your food with a little kick, add some spice to your spaghetti squash casserole. Add some red pepper flakes or diced jalapeños to the mix, or use a spicy Italian sausage.

Seafood Spin: Swap out the sausage for some shrimp or crab meat for a seafood twist.

Greek Style: Make a Greek-inspired casserole by replacing the Italian sausage with ground lamb and adding feta cheese, olives and a touch of mint.

Storage Instructions

To store, simply allow the casserole to cool and place it in an airtight container in the refrigerator for up to 5 days. Reheat in the microwave or oven.

Spaghetti Squash Casserole FAQs

Can I replace Italian sausage with another type of sausage?

Absolutely! Feel free to replace Italian sausage with chicken, turkey or vegetarian sausage for a different flavor profile.

Can I make this casserole ahead of time?

Yes, you can prepare and refrigerate your spaghetti squash casserole one day in advance. To save space in your refrigerator, transfer the mixture to a casserole dish, sprinkle with cheese, cover and refrigerate. Just bake it right before serving.

Why is my baked spaghetti squash watery?

Spaghetti squash can become watery if it's overcooked. To avoid this, during the initial roasting, bake the squash until it's just tender enough to shred with a fork but not so soft that it becomes mushy.

Why is my spaghetti squash mushy and not stringy?

Again, this could be due to overcooking. Try reducing the cooking time slightly for a more al dente, "spaghetti-like" texture.

Is spaghetti squash a high-carb vegetable?

No, spaghetti squash is considered a low-carb vegetable. One cup of cooked spaghetti squash contains about 10 grams of carbohydrates compared to the 40 grams you'd find in a cup of cooked pasta.

Does this casserole freeze well?

Yes, this spaghetti squash casserole with sausage freezes quite well. Bake as directed in a freezer-safe casserole dish. Let it cool completely, then store it in an airtight container or freezer-safe bag. It can be frozen for up to 2-3 months. Thaw in the refrigerator overnight and reheat in the oven or microwave when ready to serve.

Recipe Success Tips

Choose the Right Squash: For the best spaghetti squash casserole, look for a squash that's firm and free of blemishes or soft spots.

Don't Overcook the Spaghetti Squash: bake the squash until it's just tender enough to shred with a fork but not so soft that it becomes mushy.

If you give this recipe a try, please leave a comment below, rate the recipe, and don’t forget to tag me @homesweetfarmhome on Instagram and use the hashtag #homesweetfarmhome. I’d love to see what you come up with and share with our community. Cheers!