Gluten-Free Baked Spaghetti Squash Casserole
A hearty casserole that transforms roasted spaghetti squash into tender strands mixed with seasoned ground beef, fresh vegetables, and melted cheese. The squash is first roasted until tender but still slightly firm, then combined with browned beef, zucchini, onions, and a simple tomato sauce. Topped with generous amounts of Parmesan and Chihuahua cheese, this comforting dish bakes until bubbly and golden. Perfect for family dinners or meal prep, offering a satisfying alternative to traditional pasta bakes with fresh flavors and a satisfying texture contrast between the tender squash and hearty beef filling.
Ingredients
- 1 ½ lb spaghetti squashzucchini noodles1:1vegetable
reduce cook time significantly
- 1 tsp sea salt
- 2 ¼ lb ground beef, 80% lean
- ½ tsp garlic powder
- 1 ½ tbsp extra virgin olive oil
- 4 clove garlic, smashed
- 14 oz canned diced tomatoesmarinara sauce1:1convenience
skip garlic and seasoning steps
- 1 tsp Italian seasoning
- ¾ cup fresh Parmesan cheese, shredded
- 1 large zucchini, diced
- 1 small white onion, diced
- 4 cup Chihuahua cheese, shreddedmozzarella1:1dairy
more common substitute
Instructions
- 1
Preheat oven to 400°F and cut spaghetti squash in half lengthwise
- 2
Season squash flesh with salt and place cut side down on parchment-lined baking sheet
- 3
Roast for 30-35 minutes until flesh is soft but still slightly crunchy
- 4
Remove squash and reduce oven temperature to 350°F
- 5
Brown ground beef in nonstick skillet over medium-high heat, breaking up with spoon
- 6
Season beef with salt and garlic powder, cook 10-12 minutes until browned
- 7
Heat olive oil in saucepan over medium heat and add smashed garlic cloves
- 8
Cook garlic for 30 seconds without browning
- 9
Add diced tomatoes, salt, and Italian seasoning to garlic
- 10
Simmer tomato sauce for 5-7 minutes, taste and adjust seasoning
- 11
Scrape squash flesh into strands and combine with diced zucchini, onion, tomato sauce, beef, and Parmesan in large bowl
- 12
Mix well and taste, adding more salt as needed
- 13
Transfer mixture to 9x13 inch casserole dish
- 14
Top with Chihuahua cheese
- 15
Bake for 30 minutes until cheese is browned and casserole is heated throughout
Tips
Keep spaghetti squash slightly firm during initial roasting as it will continue cooking in the final bake, preventing mushy texture.
Brown the ground beef thoroughly and break into small pieces for even distribution throughout the casserole.
Taste the tomato sauce and adjust salt as canned tomatoes vary in sweetness and acidity.
Good to Know
Refrigerate leftovers for up to 4 days in covered container. Reheat portions in microwave or 350°F oven until warmed through.
Can assemble casserole up to 1 day ahead without final cheese topping. Cover and refrigerate, then add cheese and bake as directed.
Serve hot directly from oven. Let rest 5 minutes before serving to allow cheese to set slightly.
Common Mistakes
Avoid overcooking spaghetti squash in first step to prevent mushy final texture.
Don't brown garlic too long to avoid bitter flavor in sauce.
Let casserole rest before serving to prevent cheese from sliding off portions.
Substitutions
Dairy-Free Swaps
General Alternatives
reduce cook time significantly
FAQ
Can I make this ahead of time?
Yes, assemble the casserole without the final cheese topping up to 1 day ahead. Cover and refrigerate, then add cheese and bake as directed when ready to serve.
How long will leftovers keep?
Store covered in refrigerator for up to 4 days. Reheat individual portions in microwave or reheat larger portions in 350°F oven until heated through.
Can I freeze this casserole?
Yes, freeze assembled casserole before final baking for up to 3 months. Thaw overnight in refrigerator before baking, adding 10-15 minutes to cook time.