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Spaghetti Squash Au Gratin: A Delicious and Healthy Recipe

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4.9 from 106 reviews

This Spaghetti Squash Au Gratin recipe is a delicious and healthier twist on the classic au gratin dish. Roasted spaghetti squash strands are combined with a creamy cheese sauce made with Gruyere, sharp cheddar, and Parmesan, then baked to golden perfection with a crispy breadcrumb topping. It’s a comforting, low-carb side dish or main course that’s perfect for any occasion.

Ingredients

Scale

Spaghetti Squash

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

Creamy 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, 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

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

  • 2 tablespoons chopped fresh parsley (optional)

Instructions

  1. Preheat oven: Set your oven to 400°F (200°C) to prepare for roasting the spaghetti squash.
  2. Prepare the squash: Carefully cut the spaghetti squash in half lengthwise and scoop out all seeds and stringy bits to create hollow centers.
  3. Season the squash: Drizzle the cut sides of the squash with 2 tablespoons of melted butter and generously sprinkle with salt and black pepper to enhance flavor.
  4. Roast the squash: Place the squash halves cut-side down on a parchment-lined baking sheet. Roast in the preheated oven for 45-60 minutes, until the flesh is tender and easily pierced with a fork.
  5. Shred the spaghetti squash: After roasting and cooling slightly, use a fork to scrape the flesh into spaghetti-like strands and set aside.
  6. Melt the butter: In a large saucepan over medium heat, melt the remaining 2 tablespoons of butter to prepare for your sauce base.
  7. Sauté onion and garlic: Add the finely chopped onion to the melted butter and cook for 5-7 minutes until softened and translucent, then add minced garlic and cook for an additional minute until fragrant.
  8. Make a roux: Sprinkle the flour over the onion and garlic mixture, stirring constantly for 1-2 minutes to cook off the raw flour taste and form a roux.
  9. Whisk in milk: Gradually whisk in the whole milk bit by bit, ensuring no lumps form and the sauce becomes smooth.
  10. Simmer the sauce: Bring the sauce to a gentle simmer while stirring constantly, then reduce heat to low and cook for 5-7 minutes until it thickens slightly.
  11. Season the sauce: Stir in salt, black pepper, and nutmeg. Taste and adjust seasoning to your preference.
  12. Add cheeses: Remove the saucepan from heat. Stir in 3/4 cup Gruyere, 3/4 cup sharp cheddar, and 1/4 cup Parmesan cheese until melted into a creamy sauce.
  13. Combine squash and sauce: Add the shredded spaghetti squash strands to the cheese sauce and stir gently to combine everything thoroughly.
  14. Transfer to baking dish: Pour the cheesy spaghetti squash mixture into a greased 9×13 inch baking dish, spreading evenly.
  15. Prepare the topping: In a small bowl, mix together the remaining 1/4 cup Gruyere, 1/4 cup cheddar, 1/4 cup Parmesan cheese, and panko breadcrumbs.
  16. Sprinkle the topping: Evenly sprinkle this cheese and breadcrumb mixture over the top of the squash in the baking dish.
  17. Bake the au gratin: Place the dish back into the preheated oven and bake for 20-25 minutes until the topping is golden brown, crispy, and bubbly.
  18. Let it rest: Remove from oven and let the casserole rest for 5-10 minutes to set.
  19. Garnish and serve: Sprinkle with chopped fresh parsley if desired, serve hot, and enjoy your healthy and flavorful Spaghetti Squash Au Gratin!

Notes

  • Choose a firm, evenly shaped spaghetti squash for best results.
  • Make sure to roast the squash until very tender for easy shredding.
  • Use freshly grated cheese for the best flavor and melting quality.
  • Panko breadcrumbs add a wonderful crunch but can be substituted with regular breadcrumbs if needed.
  • You can prepare the squash ahead of time and refrigerate before assembling.
  • Consider adding cooked bacon or herbs like thyme for additional flavor variations.

Keywords: spaghetti squash au gratin, healthy au gratin, baked spaghetti squash, cheesy squash casserole, low carb squash recipe

Find it online: https://miarosetti.com/spaghetti-squash-au-gratin-a-delicious-and-healthy-recipe/