Vegan Spaghetti Squash Pizza Casserole

Name: Vegan Spaghetti Squash Pizza Casserole
Prep time: 30 min
Cook time: 25 min
Total time: 55 min
Ingredients: 1 spaghetti squash (medium-large); 1 small onion (chopped); 1/2 cup sliced mushrooms; 1/4 cup sliced black olives; 1 cup marinara sauce; 1 cup vegan shredded cheese; 1 tsp sea salt; 1/2 tsp black pepper

Modified: Jan 23, 2025 · Published: Apr 15, 2019 by Jenna Urben · This post may contain affiliate links

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This 6-ingredient spaghetti squash pizza casserole recipe is vegan and gluten free. Great for a simple weeknight dinner or meal prep.

6-Ingredient Spaghetti Squash Pizza Casserole is dairy-free, egg-free, gluten-free and vegan. This dinner casserole is low-carb, hearty, and healthy!

I realize that a lot (A LOT) of my recipes are either taco related or pizza, but I haven't heard any complaints! I could seriously live off tacos and pizza, they're just so delicious and always hit the spot.

6-Ingredient Spaghetti Squash Pizza Casserole Ingredients

Why you'll love this recipe

Loaded with veggies: This dish is filled with fresh veggies like mushroom and onion. Feel free to add other vegetables like bell pepper or spinach!
Quick and easy to make: It's seriously so simple, as the oven does most of the work. It's one of those recipes perfect for busy weeknights that also serve as an awesome lunch the next day.
Allergy friendly: Just like all of my recipes, this one is dairy free and egg free! Since there's no meat, it's also vegan and vegetarian. As an added bonus, it's also gluten free since the spaghetti squash is acting as the pasta.

6-Ingredient Spaghetti Squash Pizza Casserole How-To

Ingredient notes

Spaghetti squash: Grab a medium to large spaghetti squash at the grocery store.
Fresh vegetables: Use your favorite pizza toppings like mushrooms, onion, and black olives.
Marinara sauce: Store-bought or homemade! I prefer using marinara sauce vs pizza sauce since it's often more thin and has a richer flavor profile.
Vegan cheese: Use your favorite vegan mozzarella shredded cheese.
Seasoning: I kept this recipe pretty simple and classic, seasoning with just salt and pepper - but feel free to add some garlic powder, oregano, or even fresh basil to garnish.

How to make spaghetti squash pizza casserole

Start by cooking the spaghetti squash. Here's my guide how to cook spaghetti squash in the oven if you've never done it before. Basically, you'll first cut the ends off of the squash. Carefully slice the squash in half lengthwise and scrape the seeds out. Drizzle with olive oil and sprinkle with salt and pepper.

Place the halves onto a baking sheet and bake until tender, about 30-45 minutes. Once cooked, remove from oven and let cool slightly. Use a fork to scrape the squash and create long spaghetti-like strands.

In a large skillet, cook down the onion and mushroom, or any other pizza toppings you'll be tossing into your casserole. Add the cooked spaghetti squash, season, then transfer to a large casserole dish that's been sprayed with cooking oil.

Top with vegan shredded cheese and bake at 375F for about 25 minutes, or until cheese has melted. Remove from the oven and let cool slightly before serving. Serve with a big kale salad and dairy free dinner rolls!

6-Ingredient Spaghetti Squash Pizza Casserole

Cooking tips

Don't overcook the squash, 30-45 minutes is perfect depending on the size of the squash and your oven.
If your spaghetti squash casserole is a little too watery, place the cooked and shredded squash in a colander to drain the extra liquid.
Before slicing and serving the baked casserole, let it sit for 5-10 minutes. This will help solidify everything and ensure you don't burn your mouth!
Store leftovers in an airtight container in the refrigerator for up to 5 days.

6-Ingredient Spaghetti Squash Pizza Casserole Recipe

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