Spaghetti Squash Au Gratin Recipe

Introduction

Spaghetti Squash Au Gratin is a comforting and creamy twist on a classic dish. This recipe transforms tender roasted spaghetti squash into a cheesy, baked casserole with a golden breadcrumb crust. It’s perfect for a cozy dinner or as a side dish to impress your guests.

Ingredients

• 1 large spaghetti squash (about 3-4 pounds)
• 4 tablespoons unsalted butter, divided
• 1 medium yellow onion, finely chopped
• 2 cloves garlic, minced
• 4 tablespoons all-purpose flour
• 3 cups whole milk
• 1/2 teaspoon salt, plus more to taste
• 1/4 teaspoon black pepper, plus more to taste
• 1/4 teaspoon nutmeg
• 1 cup grated Gruyere cheese, divided
• 1 cup grated sharp cheddar cheese, divided
• 1/2 cup grated Parmesan cheese, divided
• 1/4 cup panko breadcrumbs
• 2 tablespoons chopped fresh parsley, for garnish (optional)

Instructions

1. Step 1: Preheat oven to 400°F (200°C).
2. Step 2: Cut the spaghetti squash in half lengthwise and scoop out the seeds and stringy bits.
3. Step 3: Drizzle the cut sides with 2 tablespoons melted butter, then season generously with salt and pepper.
4. Step 4: Place the squash halves cut-side down on a parchment-lined baking sheet. Roast for 45–60 minutes, until tender and easily pierced with a fork.
5. Step 5: Let the squash cool enough to handle, then use a fork to shred the flesh into spaghetti-like strands and set aside.
6. Step 6: In a large saucepan over medium heat, melt the remaining 2 tablespoons butter.
7. Step 7: Add the chopped onion and cook until softened and translucent, about 5–7 minutes. Add the minced garlic and cook for another minute until fragrant.
8. Step 8: Sprinkle the flour over the onion and garlic mixture and cook, stirring constantly, for 1–2 minutes to create a roux.
9. Step 9: Gradually whisk in the milk, a little at a time, until smooth with no lumps.
10. Step 10: Bring the sauce to a simmer, stirring constantly. Reduce heat to low and simmer for 5–7 minutes until slightly thickened.
11. Step 11: Stir in the salt, pepper, and nutmeg. Adjust seasoning to taste.
12. Step 12: Remove from heat and stir in 3/4 cup Gruyere, 3/4 cup cheddar, and 1/4 cup Parmesan until melted and creamy. Reserve remaining cheese for topping.
13. Step 13: Gently fold the shredded spaghetti squash into the cheese sauce.
14. Step 14: Pour the mixture into a greased 9×13 inch baking dish.
15. Step 15: In a small bowl, combine the remaining 1/4 cup Gruyere, 1/4 cup cheddar, 1/4 cup Parmesan, and panko breadcrumbs.
16. Step 16: Sprinkle the cheese and breadcrumb mixture evenly over the top.
17. Step 17: Bake for 20–25 minutes until the topping is golden brown and bubbly.
18. Step 18: Remove from oven and let rest for 5–10 minutes before serving.
19. Step 19: Garnish with chopped parsley if desired, then serve hot and enjoy!

Tips & Variations

• For extra flavor, add a pinch of smoked paprika or cayenne pepper to the cheese sauce.
• Swap Gruyere for mozzarella or fontina if you prefer a milder cheese.
• Use gluten-free flour and breadcrumbs to make this dish gluten-free.
• Add cooked bacon or sautéed mushrooms for a hearty twist.

Storage

Store leftovers in an airtight container in the refrigerator for up to 3 days. Reheat gently in the oven at 350°F (175°C) until warmed through to retain the crispy topping. Avoid microwaving to keep texture intact.

How to Serve

Serve this delicious recipe with your favorite sides.

FAQs

Can I prepare the spaghetti squash ahead of time?

Yes, you can roast and shred the spaghetti squash a day ahead. Keep it refrigerated until you’re ready to make the sauce and bake.

What if I don’t have fresh parsley for garnish?

The dish is flavorful on its own, but you can substitute dried parsley or chopped chives for a burst of fresh color.

Spaghetti Squash Au Gratin Recipe

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4.9 from 81 reviews

Spaghetti Squash Au Gratin is a comforting and creamy casserole that combines tender roasted spaghetti squash with a rich cheese sauce made from Gruyere, sharp cheddar, and Parmesan. The dish is topped with a crispy golden breadcrumb and cheese crust, making it a delicious low-carb alternative to traditional potato gratin. Perfect as a hearty side or a vegetarian main, this recipe offers a flavorful way to enjoy spaghetti squash with a decadent cheesy twist.

• Author: Windy
• Prep Time: 20 minutes
• Cook Time: 1 hour 15 minutes
• Total Time: 1 hour 35 minutes
• Yield: 6 servings 1x
• Category: Side Dish
• Method: Baking
• Cuisine: American
• Diet: Vegetarian

Ingredients

Scale 1x2x3x

Squash

• 1 large spaghetti squash (about 3–4 pounds)
• 2 tablespoons unsalted butter, melted (for brushing)
• Salt and black pepper, to taste

Sauce

• 2 tablespoons unsalted butter
• 1 medium yellow onion, finely chopped
• 2 cloves garlic, minced
• 4 tablespoons all-purpose flour
• 3 cups whole milk
• 1/2 teaspoon salt, plus more to taste
• 1/4 teaspoon black pepper, plus more to taste
• 1/4 teaspoon nutmeg

Cheese

• 1 cup grated Gruyere cheese, divided
• 1 cup grated sharp cheddar cheese, divided
• 1/2 cup grated Parmesan cheese, divided

Topping

• 1/4 cup panko breadcrumbs
• 2 tablespoons chopped fresh parsley, for garnish (optional)

Instructions

1. Preheat the oven: Set your oven to 400°F (200°C) to get it ready for roasting the squash and baking the gratin.
2. Prepare the squash: Cut the spaghetti squash lengthwise into two halves. Scoop out the seeds and stringy pulp from the center to create hollow cavities.
3. Season the squash: Brush the cut sides of each squash half generously with 2 tablespoons of melted butter, then sprinkle with salt and black pepper to taste for added flavor.
4. Roast the squash: Place the halves cut-side down on a parchment-lined baking sheet. Roast for 45-60 minutes until the flesh is tender and can be pierced easily with a fork.
5. Shred the squash: When cool enough to handle, use a fork to scrape and shred the flesh into spaghetti-like strands. Set aside for the sauce preparation.
6. Melt the butter: In a large saucepan over medium heat, melt the remaining 2 tablespoons of butter to start the sauce base.
7. Sauté the onion and garlic: Add the finely chopped onion and cook for 5-7 minutes until softened and translucent. Stir in minced garlic and sauté for an additional minute until fragrant.
8. Make the roux: Sprinkle the flour over the onion and garlic mixture, stirring constantly for 1-2 minutes to form a smooth roux which will thicken the sauce.
9. Whisk in the milk: Gradually add the milk a little at a time, whisking continuously to avoid lumps and achieve a smooth sauce.
10. Simmer the sauce: Bring the sauce to a gentle simmer over medium heat, stirring constantly. Reduce to low heat and cook for 5-7 minutes until it thickens slightly.
11. Season the sauce: Stir in salt, pepper, and nutmeg. Taste and adjust the seasoning as needed for a balanced flavor.
12. Add the cheese: Remove from heat and incorporate 3/4 cup of Gruyere, 3/4 cup of cheddar, and 1/4 cup of Parmesan cheese. Stir until the cheese melts and the sauce becomes creamy.
13. Combine squash and sauce: Fold the shredded spaghetti squash gently into the cheese sauce until well combined, ensuring every strand is coated.
14. Transfer to baking dish: Pour the mixture into a greased 9×13 inch baking dish, spreading it evenly.
15. Prepare the topping: In a small bowl, mix the remaining 1/4 cup Gruyere, 1/4 cup cheddar, 1/4 cup Parmesan cheese with the panko breadcrumbs to create a crunchy topping.
16. Sprinkle the topping: Evenly distribute the cheese and breadcrumb mixture over the top of the squash mixture in the baking dish.
17. Bake the gratin: Place the dish in the oven and bake for 20-25 minutes until the topping is golden brown and bubbly, indicating a perfect crust.
18. Rest before serving: Remove from the oven and allow the gratin to rest for 5-10 minutes, setting the flavors and making it easier to serve.
19. Garnish and serve: Optionally sprinkle with fresh chopped parsley for a pop of color and fresh flavor, then serve the gratin hot and enjoy your delicious meal.

Notes

• The baking time for the squash may vary depending on its size and oven; test doneness with a fork.
• You can substitute whole milk with 2% milk, but whole milk provides a richer sauce.
• For a gluten-free version, use gluten-free flour and breadcrumbs.
• Leftovers keep well refrigerated for up to 3 days and reheat nicely in the oven.
• To add a bit of protein, consider mixing in cooked bacon or ham before baking.
• If you prefer a spicier dish, add a pinch of cayenne pepper or red chili flakes to the sauce.

Keywords: spaghetti squash, au gratin, cheesy casserole, roasted squash, vegetarian recipe, comfort food