Growing up, spaghetti squash was an “on the side” affair…and even then, only if was topped with an appropriate level of butter and brown sugar. I still enjoy baked spaghetti squash this way every now and then for the sake of nostalgia—and because who am I pretending to be here? It’s delicious. I’ve also come to adore spaghetti squash as a component of more savory sides such as Roasted Spaghetti Squash with Parmesan Mushrooms and main dish recipes like Taco Spaghetti Squash Boats, Spaghetti Squash Boats with Chicken and Bacon, and today’s Italian-inspired Spaghetti Squash Casserole. The casserole filling is an easy mix of roasted and shredded spaghetti squash, diced tomatoes, bell peppers, Italian spices, and ground turkey (you can do the Spaghetti Squash Casserole with chicken instead if you prefer). All of the ingredients cook together in a single pan, and you can even get a head start by roasting the spaghetti squash up to three days in advance.

The Making of Spaghetti Squash Casserole

If spaghetti squash has been mostly a side hustle on your dinner plate too, this Spaghetti Squash Casserole with ground turkey is the perfect way to explore its versatility in main-dish recipes. The squash’s neutral flavor makes it easy to blend with a wide range of flavors, it adds bulk to just about any recipe, and it’s packed with vitamins C and A and high in fiber. It also keeps this Spaghetti Squash Casserole low carb. One serving of this healthy casserole has just 8 grams of carbs and a whopping 20 grams of protein! A shower of low-fat mozzarella on top gives this casserole that iconic bubbly, cheesy casserole “lid,” but if you are avoiding dairy or want to make this Spaghetti Squash Casserole Paleo, you can always omit it. Household members divided on the cheese? Keep it on the side and allow each person to sprinkle on his or her own.

Make Ahead and Storage Tips

To Make Ahead. Spaghetti squash can be roasted, shredded, and stored in an airtight container for up to 3 days. When ready to make the casserole, add to the filling in Step 2 as directed.To Store. Store leftovers in the refrigerator for up to 5 days.To Freeze. I haven’t tried freezing the casserole yet, but as a reader pointed out in the comments (thanks, Andrea!), spaghetti squash can get watery when thawed. If that doesn’t bother you, here’s what to do: Bake as directed, let cool, and then tightly cover and freeze for up to 3 months. Let thaw in the refrigerator overnight. Heat in a 350 degree F oven, covered, until warmed through. Uncover and bake 5 or so additional minutes, until hot and bubbly.

More Delicious Spaghetti Squash Recipes

Spaghetti Squash LasagnaTaco Spaghetti Squash BoatsSpaghetti Squash Boats with Chicken

For a little step by step, I have a new video for you below. If you try this recipe, I’d love to know what you think. Thanks as always for your kind reviews and the 5-star ratings too. I can’t say enough how much they mean to me and how helpful they are to others who might be considering the recipe too!

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