Spaghetti Squash Au Gratin : Creamy, Cheesy + Guilt-Free!

Spaghetti Squash Au Gratin

This creamy Spaghetti Squash Au Gratin is what happens when comfort food meets a healthy makeover A golden, bubbly crust over tender squash strands smothered in a luxurious cheese sauce it’s mac and cheese vibes, with way more veggies and none of the guilt!

Prep Time: 20 min
Cook Time: 70 min
Total Time: 90 min
Servings: 6–8

Ingredients

• 1 large spaghetti squash (about 3–4 lbs)
• 4 tbsp unsalted butter, divided
• 1 medium yellow onion, finely chopped
• 2 cloves garlic, minced
• 4 tbsp all-purpose flour
• 3 cups whole milk
• ½ tsp salt, plus more to taste
• ¼ tsp black pepper
• ¼ tsp nutmeg
• 1 cup grated Gruyere cheese, divided
• 1 cup grated sharp cheddar cheese, divided
• ½ cup grated Parmesan cheese, divided
• ¼ cup panko breadcrumbs
• 2 tbsp chopped fresh parsley (optional for garnish)

Step-by-Step Instructions

Roast the Squash

1. Preheat oven to 400°F (200°C).
2. Cut squash in half lengthwise, scoop out seeds.
3. Brush with 2 tbsp melted butter and season with salt & pepper.
4. Place cut-side down on parchment-lined baking sheet and roast for 45–60 minutes.
5. Once cooled slightly, fluff the strands with a fork.

Make the Cheese Sauce

6. In a large saucepan, melt 2 tbsp butter over medium heat.
7. Sauté onion until soft (5–7 min), then add garlic for 1 min.
8. Stir in flour and cook for 2 min to form a roux.
9. Slowly whisk in milk, stirring constantly.
10. Simmer until slightly thickened (5–7 min).
11. Add salt, pepper, nutmeg, then stir in ¾ cup each of Gruyere, cheddar, and ¼ cup Parmesan. Remove from heat.

Assemble + Bake

12. Combine squash strands with cheese sauce and pour into a greased 9×13″ baking dish.
13. In a bowl, mix remaining cheeses and breadcrumbs. Sprinkle over the top.
14. Bake at 400°F for 20–25 minutes until bubbly and golden.
15. Let rest for 5–10 min before serving. Garnish with parsley

Pro Tips

• Season to taste: Always taste your sauce before baking.
• Use quality cheese: Gruyere and sharp cheddar bring max flavor.
• Make it a meal: Add cooked bacon, chicken, or sausage.

Nutrition Information (Per Serving – Approx.)

Disclaimer:

Nutrition is estimated using online tools and may vary based on ingredients used.

Spaghetti Squash Au Gratin

This creamy Spaghetti Squash Au Gratin is a healthy take on comfort food with a golden crust and a luxurious cheese sauce, perfect for veggie lovers.

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Prep Time 20 minutes mins

Cook Time 1 hour hr 10 minutes mins

Total Time 1 hour hr 30 minutes mins

Servings: 7 servings

Course: Dinner, Main Course

Cuisine: American

Calories: 400

Ingredients Method Nutrition Notes

Ingredients

  

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Vegetables

• 1 large spaghetti squash (about 3–4 lbs)
• 1 medium yellow onion, finely chopped
• 2 cloves garlic, minced

Sauce Ingredients

• 4 tbsp unsalted butter, divided
• 4 tbsp all-purpose flour
• 3 cups whole milk
• ½ tsp salt, plus more to taste
• ¼ tsp black pepper
• ¼ tsp nutmeg
• 1 cup grated Gruyere cheese, divided
• 1 cup grated sharp cheddar cheese, divided
• ½ cup grated Parmesan cheese, divided

Topping

• ¼ cup panko breadcrumbs
• 2 tbsp chopped fresh parsley (optional for garnish)

Method

 

Roast the Squash

1. Preheat oven to 400°F (200°C).
2. Cut squash in half lengthwise, scoop out seeds.
3. Brush with 2 tbsp melted butter and season with salt & pepper.
4. Place cut-side down on parchment-lined baking sheet and roast for 45–60 minutes.
5. Once cooled slightly, fluff the strands with a fork.

Make the Cheese Sauce

1. In a large saucepan, melt 2 tbsp butter over medium heat.
2. Sauté onion until soft (5–7 min), then add garlic for 1 min.
3. Stir in flour and cook for 2 min to form a roux.
4. Slowly whisk in milk, stirring constantly.
5. Simmer until slightly thickened (5–7 min).
6. Add salt, pepper, nutmeg, then stir in ¾ cup each of Gruyere, cheddar, and ¼ cup Parmesan. Remove from heat.

Assemble + Bake

1. Combine squash strands with cheese sauce and pour into a greased 9×13” baking dish.
2. In a bowl, mix remaining cheeses and breadcrumbs. Sprinkle over the top.
3. Bake at 400°F for 20–25 minutes until bubbly and golden.
4. Let rest for 5–10 min before serving. Garnish with parsley.

Nutrition

Serving: 1gCalories: 400kcalCarbohydrates: 25gProtein: 18gFat: 26gFiber: 6gSugar: 9g

Notes

Season to taste: Always taste your sauce before baking. Use quality cheese: Gruyere and sharp cheddar bring max flavor. Make it a meal: Add cooked bacon, chicken, or sausage.

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