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Spaghetti Squash Au Gratin Recipe

Spaghetti Squash Au Gratin Recipe
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★★★★★

5.2 from 6 reviews

This Spaghetti Squash Au Gratin is a creamy, cheesy, and comforting baked dish that features roasted spaghetti squash strands smothered in a rich Gruyere, cheddar, and Parmesan cheese sauce, topped with a crispy panko breadcrumb crust. A delicious low-carb alternative to traditional potato gratin, perfect for a hearty vegetarian meal or side dish.

Ingredients

Scale

Spaghetti Squash

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

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 (Optional)

  • 2 tablespoons chopped fresh parsley

Instructions

  1. Preheat Oven: Preheat your oven to 400°F (200°C) to prepare for roasting the spaghetti squash and baking the au gratin.
  2. Prepare the Squash: Cut the spaghetti squash lengthwise in half and scoop out the seeds and stringy pulp inside, leaving clean halves.
  3. Season the Squash: Drizzle the cut sides with 2 tablespoons of melted butter and sprinkle generously with salt and pepper for flavor.
  4. Roast the Squash: Place the halves cut-side down on a parchment-lined baking sheet and roast for 45-60 minutes until the flesh is tender and easily pierced with a fork.
  5. Shred the Squash: Once cooled enough to handle, use a fork to scrape the flesh into spaghetti-like strands. Set aside for later use.
  6. Melt Butter: In a large saucepan over medium heat, melt the remaining 2 tablespoons of butter to start the cheese sauce base.
  7. Sauté Onion and Garlic: Add finely chopped onion and cook 5-7 minutes until softened and translucent. Stir in minced garlic and cook for 1 more minute until fragrant.
  8. Make Roux: Sprinkle the flour over the onion and garlic, stirring constantly for 1-2 minutes to cook off the raw flour taste and create a roux.
  9. Whisk in Milk: Gradually add the milk while whisking continuously to avoid lumps; continue until a smooth sauce forms.
  10. Simmer Sauce: Bring the sauce to a simmer, reduce heat to low, and cook for 5-7 minutes until slightly thickened, stirring frequently.
  11. Season Sauce: Stir in salt, black pepper, and nutmeg. Taste and adjust seasoning as needed to balance flavors.
  12. Add Cheese: Remove from heat and stir in 3/4 cup Gruyere, 3/4 cup cheddar, and 1/4 cup Parmesan until melted and creamy.
  13. Combine Squash and Sauce: Gently fold in the shredded spaghetti squash, ensuring it is evenly coated with the cheese sauce.
  14. Transfer to Baking Dish: Pour the mixture into a greased 9×13 inch baking dish, spreading it evenly.
  15. Prepare Topping: In a small bowl, mix 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 top of the squash.
  17. Bake Au Gratin: Bake in the preheated oven for 20-25 minutes until the topping is golden brown and bubbly.
  18. Rest: Remove from oven and let the dish rest for 5-10 minutes to set before serving.
  19. Garnish and Serve: Optionally garnish with chopped fresh parsley, serve hot, and enjoy your creamy spaghetti squash au gratin.

Notes

  • To save time, you can roast the spaghetti squash ahead of time and refrigerate it before assembling the dish.
  • If you prefer a sharper flavor, use extra sharp cheddar or a combination of cheeses to adjust taste.
  • The panko breadcrumb topping adds a lovely crunch but can be omitted for a gluten-free option by using gluten-free breadcrumbs or crushed nuts.
  • For a lighter version, substitute whole milk with 2% or skim milk, though the sauce will be less rich.
  • This dish can be made vegetarian by ensuring the cheese is vegetarian-friendly and the panko does not contain animal-derived ingredients.

Nutrition

Keywords: spaghetti squash, au gratin, cheesy squash casserole, vegetarian side dish, low-carb gratin, baked squash dish

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