Spaghetti Squash Pizza Casserole is a delightful low-carb dish that has transformed my weeknight dinners. Combining the comforting flavors of pizza with the health benefits of spaghetti squash, this recipe is perfect for anyone looking to enjoy a hearty meal without the carbs. With its delicious layers and nutritious ingredients, it’s sure to become a favorite for family gatherings or cozy nights in.
Why You’ll Love This Spaghetti Squash Pizza Casserole
This spaghetti squash casserole recipe is not just any casserole; it comes packed with flavor and health benefits. Here’s why you’ll fall in love with it:
- Low-carb pizza casserole with spaghetti squash is a great alternative to traditional pizza.
- It’s a delicious way to sneak vegetables into your meals.
- Perfect for meal prep; you can make it ahead and reheat.
- Family-friendly and enjoyable for kids and adults alike.
- Can be customized with toppings like pepperoni or veggies.
- Gluten-free spaghetti squash pizza casserole that everyone can enjoy.
With its Italian cuisine roots and paleo diet suitability, this dish is a versatile and satisfying meal option.
Ingredients for Spaghetti Squash Pizza Casserole
Gather these items:
- 1 medium spaghetti squash (about 3-4 pounds)
- 1 pound ground Italian sausage (mild or spicy)
- 1 ½ cups marinara sauce (no-sugar-added preferred)
- 1 ½ cups shredded mozzarella cheese
- ½ cup grated Parmesan cheese
- 1 cup diced bell peppers (red or yellow)
- ½ medium onion, diced
- 3 cloves garlic, minced
- 2 tablespoons olive oil (extra virgin preferred)
- 1 teaspoon dried Italian seasoning
- Salt and freshly cracked black pepper to taste
- Fresh basil or parsley (optional, for garnish)
How to Make Spaghetti Squash Pizza Casserole Step-by-Step
- Step 1: Preheat oven to 400°F (205°C). Cut spaghetti squash in half lengthwise, scoop out seeds, brush cut sides with olive oil, and place cut side down on a baking sheet. Roast for 35-40 minutes until tender.
- Step 2: While squash roasts, heat olive oil in a large skillet over medium heat. Sauté diced onion and bell peppers for about 5 minutes until softened. Add minced garlic and cook for 1 minute until fragrant.
- Step 3: Add ground Italian sausage to skillet, breaking it up with a spoon, and cook until browned and cooked through, about 5-7 minutes. Stir in dried Italian seasoning, salt, and pepper to taste.
- Step 4: Once squash is cool enough to handle, use a fork to shred the flesh into long strands into a large mixing bowl.
- Step 5: Add sausage and veggie mixture to the bowl with spaghetti squash. Pour in marinara sauce, 1 cup shredded mozzarella, and half of the Parmesan cheese. Mix gently to combine.
- Step 6: Lightly grease a 9×13-inch casserole dish. Transfer mixture into the dish and spread evenly. Sprinkle remaining mozzarella and Parmesan cheese on top.
- Step 7: Bake uncovered in the preheated oven for 20-25 minutes until cheese is melted and bubbly. Optionally, broil for 2-3 minutes for crispy edges, watching closely to prevent burning.
- Step 8: Remove from oven and let rest for 5 minutes. Garnish with fresh chopped basil or parsley if desired before serving.
Pro Tips for the Perfect Spaghetti Squash Pizza Casserole
Keep these in mind:
- For a vegetarian spaghetti squash pizza bake, simply replace the sausage with mushrooms or a plant-based meat alternative.
- Ensure that the spaghetti squash is fully cooked to achieve the perfect texture.
- Using a mix of cheeses can enhance the flavor; try adding cheddar for a twist.

Best Ways to Serve Spaghetti Squash Pizza Casserole
This casserole can be served in various delightful ways:
- Pair it with a side salad for a complete meal.
- Top with fresh basil or parsley for added flavor and color.
- Serve alongside garlic bread for a comforting dinner.
How to Store and Reheat Spaghetti Squash Pizza Casserole
To store leftovers, place the casserole in an airtight container in the refrigerator for up to 3 days. When ready to enjoy, simply reheat in the oven or microwave until heated through. This dish is great for meal prep and can be made ahead of time.
Frequently Asked Questions About Spaghetti Squash Pizza Casserole
What’s the secret to perfect Spaghetti Squash Pizza Casserole?
The key is to ensure the spaghetti squash is roasted properly, allowing it to become tender and easy to shred. This creates the ideal base for your casserole.
Can I make Spaghetti Squash Pizza Casserole ahead of time?
Absolutely! You can prepare the casserole a day in advance and store it in the refrigerator. Just bake it when you’re ready to serve for a quick and easy meal.
How do I avoid common mistakes with Spaghetti Squash Pizza Casserole?
Make sure not to overcook the spaghetti squash, as it can become mushy. Also, be mindful of the seasoning to enhance the overall flavor profile.
Variations of Spaghetti Squash Pizza Casserole You Can Try
There are numerous ways to customize this dish:
- For a keto spaghetti squash pizza casserole recipe, use low-carb marinara sauce and substitute cheese for a higher fat content.
- Try adding different toppings like spinach, olives, or artichokes for a Mediterranean flair.
- Experiment with different types of sausage or even chicken for a unique twist.

For more delicious recipes, check out our latest recipes or try making chocolate oatmeal bars for a sweet treat. If you’re looking for more meal prep ideas, consider our Thanksgiving green bean casserole recipe.
For more information on the health benefits of spaghetti squash, you can visit Healthline.
Print
Spaghetti Squash Pizza Casserole: 6 Layers of Flavor
- Total Time: 75 minutes
- Yield: 6 servings 1x
- Diet: Paleo
Description
A hearty, low carb, and paleo-friendly spaghetti squash casserole layered with pizza flavors, perfect for weeknights or serving guests.
Ingredients
- 1 medium spaghetti squash (about 3–4 pounds)
- 1 pound ground Italian sausage (mild or spicy)
- 1 ½ cups marinara sauce (no-sugar-added preferred)
- 1 ½ cups shredded mozzarella cheese
- ½ cup grated Parmesan cheese
- 1 cup diced bell peppers (red or yellow)
- ½ medium onion, diced
- 3 cloves garlic, minced
- 2 tablespoons olive oil (extra virgin preferred)
- 1 teaspoon dried Italian seasoning
- Salt and freshly cracked black pepper to taste
- Fresh basil or parsley (optional, for garnish)
Instructions
- Preheat oven to 400°F (205°C). Cut spaghetti squash in half lengthwise, scoop out seeds, brush cut sides with olive oil, and place cut side down on a baking sheet. Roast for 35-40 minutes until tender.
- While squash roasts, heat olive oil in a large skillet over medium heat. Sauté diced onion and bell peppers for about 5 minutes until softened. Add minced garlic and cook for 1 minute until fragrant.
- Add ground Italian sausage to skillet, breaking it up with a spoon, and cook until browned and cooked through, about 5-7 minutes. Stir in dried Italian seasoning, salt, and pepper to taste.
- Once squash is cool enough to handle, use a fork to shred the flesh into long strands into a large mixing bowl.
- Add sausage and veggie mixture to the bowl with spaghetti squash. Pour in marinara sauce, 1 cup shredded mozzarella, and half of the Parmesan cheese. Mix gently to combine.
- Lightly grease a 9×13-inch casserole dish. Transfer mixture into the dish and spread evenly. Sprinkle remaining mozzarella and Parmesan cheese on top.
- Bake uncovered in the preheated oven for 20-25 minutes until cheese is melted and bubbly. Optionally, broil for 2-3 minutes for crispy edges, watching closely to prevent burning.
- Remove from oven and let rest for 5 minutes. Garnish with fresh chopped basil or parsley if desired before serving.
Notes
- Prep Time: 15 minutes
- Cook Time: 60 minutes
- Category: Casserole
- Method: Baking
- Cuisine: Italian
Nutrition
- Serving Size: 1 serving
- Calories: 280
- Sugar: 5g
- Sodium: 700mg
- Fat: 18g
- Saturated Fat: 7g
- Unsaturated Fat: 8g
- Trans Fat: 0g
- Carbohydrates: 12g
- Fiber: 2g
- Protein: 18g
- Cholesterol: 60mg
Keywords: Spaghetti Squash Pizza Casserole