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Spaghetti Squash Au Gratin Recipe

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★★★★★

4.8 from 104 reviews

This Spaghetti Squash Au Gratin recipe offers a delightful and healthy twist on traditional au gratin dishes. Roasted spaghetti squash strands are combined with a creamy cheese sauce made from Gruyere, sharp cheddar, and Parmesan cheeses, then baked to golden perfection with a crispy breadcrumb topping. Ideal for a comforting yet nutritious meal, it’s rich in flavor while being lower in carbs than classic potato gratins.

Ingredients

Scale

Squash

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

Cheese 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
  • 1/4 teaspoon black pepper
  • 1/4 teaspoon ground nutmeg
  • 3/4 cup grated Gruyere cheese
  • 3/4 cup grated sharp cheddar cheese
  • 1/4 cup grated Parmesan cheese

Topping

  • 1/4 cup grated Gruyere cheese
  • 1/4 cup grated sharp cheddar cheese
  • 1/4 cup grated Parmesan cheese
  • 1/4 cup panko breadcrumbs

Garnish (optional)

  • 2 tablespoons chopped fresh parsley

Instructions

  1. Preheat Oven: Preheat your oven to 400°F (200°C) to get it ready for roasting the squash.
  2. Prepare the Squash: Cut the spaghetti squash in half lengthwise and scoop out the seeds and stringy bits from the center.
  3. Season the Squash: Drizzle 2 tablespoons of melted butter over the cut sides of the squash, then season generously with salt and black pepper.
  4. Roast the Squash: Place the squash halves cut-side down on a parchment-lined baking sheet. Roast for 45-60 minutes until the squash flesh is tender and easily pierced with a fork.
  5. Shred the Squash: Let the squash cool enough to handle, then use a fork to scrape out and shred the flesh into spaghetti-like strands. Set aside.
  6. Melt Butter: In a large saucepan over medium heat, melt the remaining 2 tablespoons of butter.
  7. Sauté Onion and Garlic: Add the finely chopped onion and cook for about 5-7 minutes until softened and translucent. Stir in the minced garlic and cook for an additional minute until fragrant.
  8. Make the Roux: Sprinkle the flour evenly over the onion and garlic mixture. Stir constantly and cook for 1-2 minutes to form a roux.
  9. Whisk in Milk: Gradually pour in the milk while whisking constantly to prevent lumps, creating a smooth sauce.
  10. Simmer the Sauce: Bring the sauce to a simmer over medium heat, stirring continuously. Then reduce the heat to low and simmer for 5-7 minutes until the sauce thickens slightly.
  11. Season the Sauce: Stir in 1/2 teaspoon salt, 1/4 teaspoon black pepper, and 1/4 teaspoon nutmeg. Taste and adjust the seasoning if necessary.
  12. Add Cheese: Remove the saucepan from heat and stir in 3/4 cup Gruyere, 3/4 cup sharp cheddar, and 1/4 cup Parmesan cheese until melted and the sauce is creamy.
  13. Combine Squash and Sauce: Gently fold the shredded spaghetti squash into the cheese sauce, mixing until fully combined.
  14. Transfer to Baking Dish: Pour the squash mixture into a greased 9×13 inch baking dish, spreading evenly.
  15. Prepare Topping: In a small bowl, mix together the remaining 1/4 cup Gruyere, 1/4 cup cheddar, 1/4 cup Parmesan, and panko breadcrumbs.
  16. Sprinkle Topping: Evenly distribute the cheese and breadcrumb mixture over the squash in the baking dish.
  17. Bake Au Gratin: Place the dish in the preheated oven and bake for 20-25 minutes until the topping is golden brown and bubbly.
  18. Let it Rest: Remove the dish from the oven and let it rest for 5-10 minutes to set.
  19. Garnish and Serve: Sprinkle with fresh chopped parsley if desired. Serve hot and enjoy your healthy, cheesy spaghetti squash au gratin!

Notes

  • You can substitute whole milk with 2% milk for a lighter option.
  • Ensure to roast the spaghetti squash cut-side down for moist, tender strands.
  • For gluten-free, substitute the all-purpose flour with a gluten-free flour blend and use gluten-free breadcrumbs.
  • The nutmeg adds warmth and depth to the cheese sauce but can be omitted if preferred.
  • This dish reheats well and can be stored in the refrigerator for up to 3 days.

Keywords: spaghetti squash, au gratin, healthy cheesy casserole, low carb side dish, roasted squash recipe

Find it online: https://yumwithmia.com/spaghetti-squash-au-gratin-recipe/