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Pour the spaghetti squash mixture into a greased 9×13 inch baking dish Recipe

Pour the spaghetti squash mixture into a greased 9x13 inch baking dish Recipe
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5.1 from 28 reviews

This Spaghetti Squash Au Gratin recipe offers a healthy and delicious twist on the classic cheesy casserole. Featuring tender roasted spaghetti squash tossed in a rich, creamy cheese sauce made with Gruyere, sharp cheddar, and Parmesan, then topped with a golden breadcrumb crust, it’s a comforting yet nutritious dish perfect for family dinners or special occasions.

Ingredients

Scale

Spaghetti Squash

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

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 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 the oven: Set your oven to 400°F (200°C) to prepare for roasting the squash.
  2. Prepare the squash: Cut the spaghetti squash lengthwise in half, then scoop out the seeds and stringy parts from the center.
  3. Season the squash: Drizzle the cut sides with 2 tablespoons of melted butter and season generously with salt and pepper.
  4. Roast the squash: Place the squash halves cut-side down on a parchment-lined baking sheet and roast for 45-60 minutes until the flesh is tender and can be easily pierced with a fork.
  5. Shred the squash: Allow the squash to cool enough to handle, then use a fork to shred the flesh into spaghetti-like strands. Set aside.
  6. Melt the 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 to the melted butter and cook for 5-7 minutes until softened and translucent. Add minced garlic and cook for an additional minute until fragrant.
  8. Create a roux: Sprinkle the flour over the onion and garlic mixture and cook, stirring constantly, for 1-2 minutes to form a roux.
  9. Whisk in the milk: Gradually add milk while whisking continuously to avoid lumps, creating a smooth sauce.
  10. Simmer the sauce: Bring the sauce to a gentle simmer, stirring constantly. Lower the heat and continue to simmer for 5-7 minutes until slightly thickened.
  11. Season the sauce: Stir in salt, pepper, and nutmeg. Taste and adjust seasoning as needed.
  12. Add the cheeses: Remove the sauce from heat and mix in 3/4 cup Gruyere, 3/4 cup cheddar, and 1/4 cup Parmesan until melted and the sauce is creamy.
  13. Combine squash and sauce: Add the shredded spaghetti squash to the cheese sauce and gently stir to combine well.
  14. Transfer to baking dish: Pour the 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, and panko breadcrumbs.
  16. Sprinkle the topping: Evenly sprinkle the cheese and breadcrumb mixture over the squash in the baking dish.
  17. Bake the au gratin: Place the dish into the preheated oven and bake for 20-25 minutes until the topping is golden brown and bubbly.
  18. Rest before serving: Remove the dish from the oven and let it rest for 5-10 minutes to set.
  19. Garnish and serve: Optionally, sprinkle chopped fresh parsley on top and serve hot. Enjoy your delicious Spaghetti Squash Au Gratin!

Notes

  • For a lighter version, substitute whole milk with 2% or skim milk, but the sauce may be less rich.
  • Feel free to add cooked bacon or sautéed mushrooms for added flavor and texture.
  • Panko breadcrumbs ensure a crisp topping but regular breadcrumbs can be used instead.
  • Make sure the spaghetti squash is fully roasted and tender to easily shred into strands.
  • Leftovers can be refrigerated for up to 3 days and reheated in the oven to maintain crispness.
  • For a gluten-free version, use gluten-free flour and breadcrumbs.

Nutrition

Keywords: spaghetti squash, au gratin, healthy casserole, cheesy squash bake, vegetarian side dish, comfort food

Find it online: https://liamjayne.com/pour-the-spaghetti-squash-mixture-into-a-greased-9x13-inch-baking-dish-recipe/