Name: Spaghetti Squash Au Gratin Recipe
Prep time: 15 min
Cook time: 1 h 25 min
Total time: 1 h 40 min
Cuisine: American
Ingredients: 1 large spaghetti squash (about 3-4 pounds); 2 tablespoons unsalted butter, melted (for drizzling); Salt and 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

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Introduction

Spaghetti Squash Au Gratin is a comforting and healthier twist on the classic cheesy casserole. This dish features tender roasted spaghetti squash strands baked in a rich, creamy cheese sauce with a crispy breadcrumb topping. It’s perfect for a cozy dinner or as a side dish to impress your guests.

A white oval baking dish filled with a two-layer baked spaghetti squash casserole is held by a woman's hand wearing a red knitted pot holder. The bottom layer is bright yellow shredded spaghetti squash, soft and fibrous in texture. The top layer is melted white cheese, creamy with light golden brown spots and small green herb bits scattered across, covering the squash evenly. The dish rests on a wooden trivet on a white marbled surface, with white garlic bulbs and a red and white striped cloth in the background. photo taken with an iphone --ar 4:5 --v 7

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

Step 1: Preheat the 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 and sprinkle generously with salt and pepper. Place the squash halves cut-side down on a parchment-lined baking sheet.
Step 3: Roast the squash for 45-60 minutes, until it is tender and easily pierced with a fork.
Step 4: When cool enough to handle, use a fork to shred the flesh into spaghetti-like strands and set aside.
Step 5: In a large saucepan over medium heat, melt the remaining 2 tablespoons of butter. Add the chopped onion and cook until softened and translucent, about 5-7 minutes.
Step 6: Add the minced garlic and cook for another minute, until fragrant.
Step 7: Sprinkle the flour over the onion and garlic and cook, stirring constantly, for 1-2 minutes to create a roux.
Step 8: Gradually whisk in the milk, a little at a time, ensuring no lumps form. Continue whisking until the sauce is smooth.
Step 9: Bring the sauce to a simmer over medium heat, stirring constantly. Reduce heat to low and simmer for 5-7 minutes until slightly thickened.
Step 10: Stir in salt, pepper, and nutmeg. Taste and adjust seasonings as needed.
Step 11: Remove from heat and stir in 3/4 cup Gruyere, 3/4 cup cheddar, and 1/4 cup Parmesan until melted and the sauce is creamy.
Step 12: Add the shredded spaghetti squash to the cheese sauce and gently stir to combine.
Step 13: Pour the mixture into a greased 9×13-inch baking dish.
Step 14: In a small bowl, combine the remaining 1/4 cup Gruyere, 1/4 cup cheddar, 1/4 cup Parmesan, and panko breadcrumbs.
Step 15: Sprinkle this cheese and breadcrumb topping evenly over the spaghetti squash mixture.
Step 16: Bake in the oven for 20-25 minutes, until the topping is golden brown and bubbly.
Step 17: Remove from the oven and let rest for 5-10 minutes before serving.
Step 18: Garnish with chopped fresh parsley if desired, serve hot, and enjoy your delicious Spaghetti Squash Au Gratin!

Tips & Variations

For a gluten-free version, substitute the all-purpose flour with a gluten-free flour blend and use gluten-free breadcrumbs.
Add cooked bacon or sautéed mushrooms for extra flavor and texture.
Use a mix of your favorite cheeses such as mozzarella or fontina to vary the taste.
To enhance the creaminess, stir in a little cream cheese or mascarpone into the sauce before baking.

Storage

Store leftovers in an airtight container in the refrigerator for up to 3 days. Reheat in the oven at 350°F (175°C) until warmed through to maintain the crispy topping, or microwave in shorter intervals if preferred.

How to Serve

The image shows a white plate with a textured design around the edge, holding a triangular slice of a golden brown, baked dish with a crispy top layer. The dish has a soft, slightly shredded yellowish base with melted cheese that appears bubbly and browned in spots. A silver fork rests on the plate with a small bite of the dish on its tines, hinting at a creamy, moist inside. In the background, a white pie dish with the remaining baked dish sits slightly out of focus on a white marbled surface, next to a green cloth napkin. There is also a woven basket with pastel-colored eggs partially visible in the top left corner. Photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I prepare this dish ahead of time?

Yes, you can assemble the casserole and refrigerate it for up to 24 hours before baking. Just add a few extra minutes to the baking time if baking from cold.

Is spaghetti squash good for this recipe instead of pasta?

Absolutely! Spaghetti squash is a healthy, low-carb alternative that works perfectly with a cheesy au gratin sauce, offering a similar texture to pasta.