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A close-up shot showcases a creamy and delicious serving of Spaghetti Squash Au Gratin, perfect for a comforting meal.

Spaghetti Squash Au Gratin Easy

This Spaghetti Squash Au Gratin is a comforting and surprisingly simple dish. Tender spaghetti squash strands are bathed in a creamy, cheesy sauce and baked until golden brown and bubbly. It's an elevated comfort food that's sure to become a family favorite.
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Prep Time 25 minutes
Cook Time 1 hour 5 minutes
Total Time 1 hour 30 minutes
Servings: 6
Course: Main Course
Cuisine: American
Calories: 400
Ingredients Equipment Method Notes

Ingredients
  

  • 1 large spaghetti squash about 2-3 pounds
  • 1 tablespoon olive oil
  • 1/2 teaspoon salt
  • 1/4 teaspoon black pepper
  • 4 tablespoons butter
  • 4 tablespoons all-purpose flour
  • 3 cups milk whole or 2%
  • 1/4 teaspoon nutmeg
  • 1/2 teaspoon salt
  • 1/4 teaspoon black pepper
  • 1 cup shredded Gruyere cheese
  • 1 cup shredded sharp cheddar cheese
  • 1/2 cup grated Parmesan cheese, divided

Equipment

  • Chef's knife
  • cutting board
  • baking sheet
  • parchment paper
  • medium saucepan
  • whisk
  • Large bowl
  • 9x13-inch baking dish
  • Oven

Method
 

  1. Preheat your oven to 400°F (200°C).
  2. Cut the spaghetti squash in half lengthwise. Scoop out the seeds and stringy bits.
  3. Drizzle the cut sides with olive oil and season with salt and pepper.
  4. Place the squash cut-side down on a baking sheet lined with parchment paper.
  5. Roast for 40-50 minutes, or until the squash is easily pierced with a fork and the flesh is tender.
  6. In a medium saucepan, melt the butter over medium heat.
  7. Whisk in the flour and cook for 1-2 minutes, stirring constantly, to create a roux.
  8. Slowly pour in the milk, whisking constantly to prevent lumps. Keep whisking until the sauce thickens, about 5-7 minutes.
  9. Remove from heat and stir in the nutmeg, salt, and pepper.
  10. Add the Gruyere, cheddar, and half of the Parmesan cheese to the sauce. Stir until the cheese is melted and the sauce is smooth and creamy. Taste and adjust seasonings as needed.
  11. Once the squash is cool enough to handle, use a fork to scrape the flesh into strands.
  12. In a large bowl, gently toss the spaghetti squash strands with the au gratin sauce. Make sure everything is well combined.
  13. Pour the squash mixture into a greased 9x13 inch baking dish.
  14. Sprinkle the remaining Parmesan cheese over the top.
  15. Bake in the preheated oven for 20-25 minutes, or until the top is golden brown and bubbly.
  16. Let cool for a few minutes before serving.

Notes

For easier cutting, microwave the spaghetti squash for 3-4 minutes before cutting. Store leftovers in an airtight container in the refrigerator for up to 3 days. Reheat in the oven at 350°F (175°C) until heated through, about 15-20 minutes. Variations: Add cooked bacon, sausage, chicken, ham, sauteed mushrooms, onions, spinach or roasted bell peppers. Add red pepper flakes or smoked paprika for extra flavor. Fontina, provolone, or Monterey Jack can be substituted for Gruyere or cheddar.