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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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4.9 from 16 reviews

Spaghetti Squash Au Gratin is a comforting and healthy twist on the classic au gratin dish. This recipe combines tender roasted spaghetti squash strands with a creamy, cheesy sauce made from Gruyere, sharp cheddar, and Parmesan, topped with a golden, crispy breadcrumb crust. It’s a delicious, low-carb alternative that retains all the rich, indulgent flavors, perfect as a vegetarian main or a hearty side dish.

Ingredients

Scale

Spaghetti Squash

  • 1 large spaghetti squash (about 3–4 pounds)
  • 2 tablespoons unsalted butter, melted (for squash seasoning)
  • Salt and 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
  • 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 prepare for roasting the spaghetti squash.
  2. Prepare the Spaghetti Squash: Cut the spaghetti squash in half lengthwise and carefully scoop out the seeds and stringy bits from each half.
  3. Season the Squash: Drizzle the cut sides of the squash with 2 tablespoons of melted butter, then sprinkle generously 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 and roast for 45-60 minutes until the flesh is tender and easily pierced with a fork.
  5. Shred the Squash: Once cool enough to handle, use a fork to shred the cooked squash 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 unsalted butter to start the 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 the minced garlic and cook for another minute until fragrant.
  8. Make the Roux: Sprinkle the flour over the onion and garlic mixture and cook while stirring continuously for 1-2 minutes to form a roux.
  9. Whisk in Milk: Gradually add the whole milk a little at a time, whisking constantly to ensure a smooth sauce without lumps.
  10. Simmer the Sauce: Bring the sauce to a gentle simmer over medium heat, stirring constantly, then reduce heat to low and simmer for 5-7 minutes until slightly thickened.
  11. Season the Sauce: Stir in salt, black pepper, and nutmeg; taste and adjust seasonings as needed.
  12. Add Cheese to Sauce: Remove the saucepan from the heat and stir in 3/4 cup Gruyere, 3/4 cup sharp cheddar, and 1/4 cup Parmesan cheese until melted and creamy.
  13. Combine Squash & Sauce: Gently fold the shredded spaghetti squash into the cheese sauce until evenly coated.
  14. Transfer to Baking Dish: Pour the squash and cheese mixture into a greased 9×13 inch baking dish, spreading it evenly.
  15. Prepare the Topping: In a small bowl, mix the remaining 1/4 cup Gruyere, 1/4 cup sharp cheddar, 1/4 cup Parmesan cheese, and 1/4 cup panko breadcrumbs together.
  16. Apply the Topping: Evenly sprinkle the cheese and breadcrumb topping over the prepared spaghetti squash mixture 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. Rest Before Serving: Remove the au gratin from the oven and let it rest for 5-10 minutes to set.
  19. Garnish and Serve: Optionally garnish with chopped fresh parsley, then serve hot and enjoy your healthy, delicious spaghetti squash au gratin!

Notes

  • Be careful when cutting the spaghetti squash as it has a tough exterior; use a sharp, sturdy knife.
  • Roasting times may vary depending on the size of your squash; test tenderness with a fork.
  • Feel free to substitute dairy milk with unsweetened plant-based milk for a lactose-free version, adjusting cheese accordingly.
  • For extra flavor, add a pinch of smoked paprika or cayenne pepper to the cheese sauce.
  • Leftovers can be stored in an airtight container in the refrigerator for up to 3 days and reheated in the oven for best results.

Nutrition

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

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