Name: Alfredo Spaghetti Squash Casserole (5 Ingredients!)
Prep time: 5 min
Cook time: 40 min
Total time: 45 min
Ingredients: 2 large spaghetti squash; 2 cups broccoli florets (150 g); 2 Tbsp olive oil (30 mL); 1 16-oz jar Alfredo sauce (about 1 ½ cups, 453 g); 1 cup shredded mozzarella cheese (divided, 100 g)

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Made with just 5 ingredients, Alfredo spaghetti squash casserole is filled with undeniable flavor while still being low in carbs! It’s so easy to make and with such classic flavors that it’s always a hit at the dinner table. This dish doesn’t play around.

A close-up shot of a dish of spaghetti squash Alfredo casserole

There’s something to be said for coming home from a long day of work, putting together a quick casserole, plopping it in the oven for a bit, and then enjoying a nice, warm bowl of creamy, cheesy, savory delight.

And that’s exactly what this spaghetti squash Alfredo casserole does. Trust me, you’re gonna love it.

Cheesy: It’s cheesy, jam-packed with veggies, and oh, so delicious. You’d never know it’s low in carbs.
Minimal Ingredients: You don’t need many ingredients to bring the flavor, just the right ingredients.
Simple to Make: You just roast, mix, and broil. With no proteins to cook, this recipe is also super fast.

Reader rating

★★★★★

“This recipe was the only way my family have ever eaten more than a bite of spaghetti squash so this must be good! I liked it.” —Dara

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A white bowl filled with a serving of spaghetti squash Alfredo casserole

Here’s what you’ll need

I love a good low-ingredient recipe, and this one fits the bill each and every time. This means less time spent gathering items at the grocery store and more time spent enjoying each savory bite of this squash casserole. Jump to the recipe card for exact measurements and substitutions.

Spaghetti Squash: To start this recipe, snag two large, bright yellow spaghetti squash. Choose two that are void of soft spots and feel firm to the touch.
Broccoli: Next in this recipe, we’ll use 2 cups of broccoli florets. Fresh works best, but cauliflower would also work well here!
Olive Oil: We will use olive oil to crisp up the spaghetti squash and the broccoli in the oven.
Alfredo Sauce: Rather than making it from scratch, we’re opting for store-bought stuff (because who has time for that on a weeknight?). Choose your favorite Alfredo. 16-oz of any brand or recipe will work.
Shredded Mozzarella Cheese: Mix half of it into the casserole to lace your Alfredo casserole with cheesy deliciousness. Sprinkle the rest on top and broil to crispy brown perfection.

A casserole dish filled with cooked spaghetti squash Alfredo casserole

Freeze it!

This recipe makes a great freezer dish. Make it completely, let it cool, then freeze it. You can either freeze it in an aluminum tray, a freezer-safe baking dish, or a ziplock bag laid flat. When you want to enjoy it, reheat it from frozen or pop the frozen block into a slow cooker to reheat throughout the day.

flavorful variations

When making your casserole, there are a number of ways that you can customize it and add ingredients to make it your very own.

Add veggies like green peppers, red onions, or even sautéed mushrooms.
Add chickpeas, crispy air fryer chickpeas especially, are a fun addition to this dish (similar to how we do in this vegan chickpea alfredo recipe).
Add protein by making the cottage cheese alfredo sauce from this casserole instead of using store bought here.

more spaghetti squash recipes

Low Carb Spaghetti Squash Mac and Cheese

45 minutes

Spaghetti Squash Burrito Bowls

1 hour

Spaghetti Squash with Goat Cheese and Mushrooms

1 hour

Pesto Spaghetti Squash Bowls

45 minutes

A wooden spoon serves a portion of creamy spaghetti squash alfredo casserole, topped with cheese and sprinkled with herbs in a clear glass baking dish.

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