Description
A hearty and comforting Spaghetti Squash Casserole featuring roasted spaghetti squash strands mixed with a savory ground turkey and spinach filling, all enveloped in a creamy Gruyere cheese sauce, baked to perfection with a crispy topping of French fried onions.
Ingredients
Units
Scale
Casserole Ingredients
- 2 (roughly 3 pound) spaghetti squash, halved and seeds discarded
- Olive oil (several tablespoons for roasting and sautéing)
- Salt (to taste)
- Black pepper (to taste)
- 1/2 teaspoon granulated onion
- 1/2 teaspoon granulated garlic
- 1 medium onion, quartered and thinly sliced
- 1/2 pound ground turkey
- 1/4 teaspoon white pepper
- 4 cloves garlic, pressed through garlic press
- 2 cups (packed) baby spinach leaves
- 1 1/2 tablespoons chopped fresh sage leaves
- 1 teaspoon fresh thyme leaves, plus extra for garnish
- 3/4 cup grated Gruyere cheese (divided)
- 1/2 cup crispy French fried onions
Creamy Gruyere Sauce Ingredients
- 3 tablespoons unsalted butter
- 2 cloves garlic, pressed through garlic press
- 5 tablespoons (level) flour (roughly 1 1/2 ounces)
- 3 cups whole milk
- Salt (to taste)
- Black pepper (to taste)
- 1 teaspoon Italian seasoning
- Pinch nutmeg
- 1/4 cup grated Gruyere cheese
Instructions
- Preheat and Prepare Squash: Preheat oven to 400°F and line a large baking sheet with foil. Drizzle olive oil over cut sides of halved spaghetti squash, and season with salt, black pepper, granulated onion, and granulated garlic. Place cut-side down on the baking sheet and roast for about 1 hour or until easily pierced with a skewer.
- Cook Turkey Mixture: While squash roasts, heat 3 tablespoons olive oil in a large skillet over medium-high heat. Add sliced onions, salt, and pepper, sautéing for about 10 minutes until golden brown. Add ground turkey, salt, pepper, and white pepper; crumble and cook for 2-3 minutes until deep golden brown. Stir in pressed garlic, spinach leaves and cook until the spinach wilts (30 seconds to 1 minute). Mix in chopped sage and thyme. Remove from heat and set aside.
- Prepare Spaghetti Squash: Once roasted, let squash cool for 20 minutes until easily handled. Reduce oven temperature to 375°F. Use a fork to scrape flesh into strands and transfer to a large bowl.
- Make Gruyere Sauce: In a medium-large pot over medium heat, melt butter with garlic. Whisk in flour to form a roux. Gradually whisk in milk to avoid lumps. Bring to a vigorous simmer and cook 2-3 minutes until thickened. Turn off heat and season with salt, black pepper, Italian seasoning, and nutmeg. Stir in ¼ cup grated Gruyere cheese until melted and smooth.
- Combine Casserole Mixture: Add spaghetti squash strands and turkey/onion/spinach mixture into the sauce. Stir gently until well combined. Adjust salt and pepper if needed.
- Assemble and Bake: Lightly spray a 3-quart baking dish with cooking spray. Spoon combined casserole mixture into dish. Sprinkle ¾ cup grated Gruyere over the top. Bake uncovered at 375°F for 20 minutes.
- Add Topping and Finish Baking: After 20 minutes, sprinkle French fried onions evenly on top. Bake for an additional 5 minutes until topping is crispy and cheese is bubbly.
- Garnish and Serve: Remove casserole from oven, garnish with fresh thyme leaves, and serve warm.
Notes
- You can substitute ground turkey with ground chicken or beef if preferred.
- If you prefer a milder sauce, reduce the amount of garlic in the sauce.
- Make sure not to skip letting the squash cool enough to handle for easier shredding.
- French fried onions add a crunchy texture – substitute with breadcrumbs if unavailable.
- Leftovers can be refrigerated for up to 3 days and reheated in the oven for best results.
