Name: Spaghetti Squash Au Gratin Recipe
Prep time: 20 min
Cook time: 1 h 10 min
Total time: 1 h 30 min
Cuisine: American
Ingredients: 1 large spaghetti squash (about 3–4 pounds); 2 tablespoons unsalted butter, melted (for roasting); Salt and freshly ground black pepper, to taste; 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; 3/4 cup grated Gruyere cheese; 3/4 cup grated sharp cheddar cheese; 1/4 cup grated Parmesan cheese; 1/4 cup grated Gruyere cheese; 1/4 cup grated sharp cheddar cheese; 1/4 cup grated Parmesan cheese; 1/4 cup panko breadcrumbs; 2 tablespoons chopped fresh parsley (optional)

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Introduction

Spaghetti Squash Au Gratin is a delicious, creamy, and healthier twist on the classic comfort food. This recipe combines tender roasted squash with a rich cheese sauce, topped with a golden, crispy crust. It’s perfect for a cozy dinner that feels indulgent yet light.

A cooked half spaghetti squash with a golden yellow shell and a slightly browned edge, filled with a creamy, light yellow cheese sauce topped with melted, bubbly cheese that is browned in spots and sprinkled with small green herb bits. A fork held by a woman's hand lifts a stringy, gooey portion of the cheesy filling from the center. The squash is placed on a white square plate, which sits on a white marbled surface. photo taken with an iphone --ar 4:5 --v 7

Ingredients

1 large spaghetti squash (about 3–4 pounds)
2 tablespoons unsalted butter, melted (for roasting)
Salt and freshly ground black pepper, to taste
2 tablespoons unsalted butter (for sauce)
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
3/4 cup grated Gruyere cheese
3/4 cup grated sharp cheddar cheese
1/4 cup grated Parmesan cheese
1/4 cup grated Gruyere cheese (for topping)
1/4 cup grated sharp cheddar cheese (for topping)
1/4 cup grated Parmesan cheese (for topping)
1/4 cup panko breadcrumbs
2 tablespoons chopped fresh parsley (optional, for garnish)

Instructions

Step 1: Preheat your oven to 400°F (200°C). Cut the spaghetti squash in half lengthwise and scoop out the seeds and stringy bits.
Step 2: Drizzle the cut sides of the squash with 2 tablespoons melted butter. Season generously with salt and freshly ground black pepper.
Step 3: 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.
Step 4: Let the squash cool slightly, then use a fork to scrape the flesh into spaghetti-like strands. Set aside.
Step 5: In a large saucepan over medium heat, melt 2 tablespoons butter. Add the chopped onion and cook for 5-7 minutes until softened and translucent. Stir in minced garlic and cook for 1 minute until fragrant.
Step 6: Sprinkle the flour over the onion and garlic mixture. Stir constantly for 1-2 minutes to form a roux and cook off the raw flour taste.
Step 7: Gradually whisk in the whole milk, adding it bit by bit. Stir constantly until the sauce is smooth.
Step 8: Bring the sauce to a gentle simmer, stirring frequently. Reduce heat to low and cook for 5-7 minutes until thickened slightly.
Step 9: Season the sauce with salt, black pepper, and nutmeg. Adjust seasoning to taste.
Step 10: Remove the saucepan from heat. Stir in 3/4 cup Gruyere, 3/4 cup sharp cheddar, and 1/4 cup Parmesan cheese until melted and creamy.
Step 11: Add the shredded spaghetti squash to the cheese sauce. Gently stir to combine thoroughly.
Step 12: Pour the mixture into a greased 9×13 inch baking dish and spread evenly.
Step 13: In a small bowl, mix together 1/4 cup Gruyere, 1/4 cup sharp cheddar, 1/4 cup Parmesan, and panko breadcrumbs.
Step 14: Sprinkle the cheese and breadcrumb topping evenly over the squash mixture.
Step 15: Bake in the preheated oven for 20-25 minutes until the topping is golden brown, crispy, and bubbly.
Step 16: Remove from oven and let rest for 5-10 minutes to set.
Step 17: Garnish with chopped fresh parsley if desired. Serve hot and enjoy your Spaghetti Squash Au Gratin!

Tips & Variations

For a lighter version, substitute whole milk with 2% or unsweetened almond milk, but creaminess may vary.
Add cooked bacon or pancetta in step 11 for a smoky flavor boost.
Use gluten-free flour and breadcrumbs to make this dish gluten-free.
To easily shred the squash, cool it just enough to handle but still warm when scraping with a fork.
Try mixing different cheeses like fontina or mozzarella for variation in taste and texture.

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, about 15-20 minutes, to maintain the crispy topping. Avoid microwaving to keep the texture crispy.

How to Serve

A halved yellow spaghetti squash acts as a natural bowl, filled with soft, tender squash strands that are covered by a golden-browned, bubbly, melted cheese layer. The cheese is creamy white with spots of deep amber from baking, and it stretches as a silver fork lifts a portion of the cheesy squash from the center of the squash half. This squash bowl sits on a white marbled surface, and the focus is on the rich, gooey texture of the cheese and the fibrous strands inside the squash. photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I prepare Spaghetti Squash Au Gratin in advance?

Yes, you can prepare the casserole up to the baking step, cover it, and refrigerate for up to 24 hours. Bake it fresh before serving, adding a few extra minutes if baking from cold.

What if I don’t have Gruyere cheese?

You can substitute Gruyere with Emmental or Swiss cheese, which have a similar melt and nutty flavor. Cheddar alone works as well but will change the flavor profile slightly.